APA 7th Citation Examples

In-text example
... Organisation (Abbreviation, year, p. xx) ...

The American Water Works Association (AWWA, 2004, p. xx) recommends that ...

Reference list example
Organisation. (year). Book title in italics (xx ed.).

American Water Works Association. (2004). Sizing water service lines and meters:
      Manual of water supply practices ‑ M22 (2nd ed.).

Remark
1. When author and publisher are the same, omit the publisher name.
2. The name of an organization is fully spelled in the first in-text citation, in the following citations an abbreviation is used: Abbreviation (year) ....

In-text example
Author (year, p. xx) ...

Dorf (2006, p. 51)

Reference list example
Author, A. A. (year). Book title in italics (xx ed.). Publisher.

Dorf, R. C. (2006). The electrical engineering handbook (3rd ed.). CRC/Taylor & Francis.

Remark
Place information about editions, volume numbers, and page numbers in parentheses with the period after the parentheses: (Rev. ed.). or (Vol. xx, pp. xxx-xxx).

In-text example
... (Author & Author, year, p. xx) ...

... to achieve consistency (Spellman & Drinan, 2005, p. xx).

Reference list example
Author, A. A., & Author, B. (year). Book title in italics. Publisher.

Spellman, F. R., & Drinan, J. (2005). The drinking water handbook. Technomic.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
Author et al. (year, p. xx) ...

Anderson et al. (2006, p. xx)

Reference list example
Author, A. A., Author, B. B., & Author, C. C. (year). Book title in italics. Publisher.

Anderson, D. R., Sweeney, D. J., & Williams, T. A. (2006). Quantitative methods for business. Thomson SouthWestern.

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
(B. B. Author, year, p. xx) ...
(A. A. Author, year, p. xx) ...

(P. M. Anderson, 2003, p. xx)
(J. B. Anderson, 2005, p. xx)

Reference list example
Author, A. A. (year). Book title in italics. Publisher.
Author, B. B. (year). Book title in italics. Publisher.

Anderson, J. B. (2005). Digital transmission engineering. IEEE Press.
Anderson, P. M. (2003). Analysis of faulted power systems. IEEE Press.

Remark
If a reference list includes publications by authors with the same last name, include the author's initials in all-in-text citations, even if the year of publication is different.

In-text example
(Author, year, p.xx; year, p. yy) ...

(Smith, 2005, p. xx; 2007, p. yy)

Reference list example
Author, A. (year). Book title in italics. Publisher.
Author, A. (year). Book title in italics. Publisher.

Smith, P. (2005). Piping Materials Guide. Elsevier.
Smith, P. (2007). Process piping design handbook: Fundamentals of piping design. Gulf.

Remark
Arrange two or more works bij the same author by year of publication.

In-text example
(Author, yeara, p.xx; yearb, p. yy) ...

(Napier, 1993a, p. xx; 1993b, p. yy) ...

Reference list example
Author, A. (yeara). Book title in italics. Publisher.
Author, A. (yearb). Book title in italics. Publisher.

Napier, A. (1993a). Fatal storm. Allen & Unwin.
Napier, A. (1993b). Survival at sea. Allen & Unwin.

Remark
Identify works by the same author with the same publication year by the suffixes a, b, c, ...

In-text example
Author ( year, p. xx) ...

Ardia (2008, p. xx)

Reference list example
Author, A. (year). Book title in italics. Publisher. https://doi.org/xxxxx

Ardia, D. (2008). Financial risk management with Bayesian estimation of GARCH models: Theory and applications. 
      Springer. https://doi.org/10.1007/978‑3‑540‑78657‑3

Remark
Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
(Author & Author, year, p. xx) ...

(Zhang & Schwaerzel, 2017, p. 138)

Reference list example
Author, A., & Author, B. (year). Book title in italics. Publisher. https://doi.org/xxxxx

Zhang, L., & Schwaerzel, K. (2017). Multifunctional land‑use systems for managing the nexus of environmental
      resources. Springer. https://doi.org/10.1007/978‑3‑319‑54957‑6

Remark
1. Use the ampersand only in the parenthetical format of the in-text citation.
2. Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
Author et al. (year)

Earle et al. (2015)

Reference list example
Author, A., Author, B. B., Author, C., Author, D., Author, E., & Author, F. (year). Book title in italics. Publisher.
      https://doi.org/xxxxx

Earle, A., Cascao, A. E., Hansson, S., Jaegerskog, A., Swain, A., & Ojendal, J. (2015). Transboundary water
      management and the climate change debate. Routledge. https://doi.org/10.4324/9780203098929

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.
3. Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
Author ( year, p. xx) ...

Edwards (2008, p. xx)

Reference list example
Author, A. A. (year). Book title in italics (Vol. xx). Publisher. https://xxxxx

Edwards, P. N. (2008). How to read a book (Vol. 5.0). University of Michigan. 
      http://pne.people.si.umich.edu/PDF/howtoread.pdf

Remark
1. For works without DOIs from websites (not including databases), use a URL in the reference.
2. For works without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed book.

In-text example
(Author & Author, year, p. xx) ...

(Grafton & Hussey, 2011, p. 5)

Reference list example
Author, A. A. & Author, B. (year). Book title in italics. Publisher. https://xxxxx

Grafton, R. Q., & Hussey, K. (2011). Water resources planning and management. Cambridge University Press. 
      https://www.amazon.com/Resources‑Planning‑Management‑Quentin‑Grafton‑dp‑21762588/dp/0521762588/

Remark
1. Use the ampersand only in the parenthetical format of the in-text citation.
2. For works without DOIs from websites (not including databases), use a URL in the reference.
3. For works without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed book.

In-text example
Author et al. (year) ...

Sutt et al. (2013)

Reference list example
Author, A., Author, B., & Author, C. (year). Book title in italics. Publisher. https://xxxxx

Sutt, J., Lill, I., & Muursepp, O. (2013). The engineer's manual of construction site planning. Wiley. 
      https://www.amazon.com/Engineers‑Manual‑Construction‑Site‑Planning‑dp‑1118556097/dp/1118556097/

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.
3. For works without DOIs from websites (not including databases), use a URL in the reference.
4. For works without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed book.

In-text example
Author ( year, p. xx) ...

Breach (2012, p. 37)

Reference list example
Author, A. (Ed). (year). Book title in italics. Publisher.

Breach, B. (Ed.). (2012). Drinking water quality management from catchment to consumer: A practical guide for utilities
      based on water safety plans. IWA.

Remark

In-text example
Author and Author (year)

Blockley and Shyy (2010)

Reference list example
Author, A., & Author, B. (Eds). (year). Book title in italics (xx ed., Vol. xx). Publisher.

Blockley, R., & Shyy, W. (Eds.). (2010). Encyclopedia of aerospace engineering (6th ed., Vols. 1‑9). Wiley.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
Author et al. (year) ...

Hong et al. (2014)

Reference list example
Author, A., Author, B., Author, C., & Author, D. (Eds). (year). Book title in italics. Publisher.

Hong, C., Moorman, G., Wohanka, W., & Buettner, C. (Eds.). (2014). Biology, detection, and management of
      plant pathogens in irrigation water. American Phytopathological Society.

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2.For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
Author (year) ...

Gibson (2011)

Reference list example
Author, A. A. (year). Title of chapter. In E. Editor (Ed.), Book title in italics. (pp. xx). Publisher.

Gibson, C. C. (2011). Impact of the larger social context on the distance learner. In S. Allsop (Ed.),
      International Council for Distance Education: One world many voices: Quality in open and
      distance learning (pp. 279‑282). Milton Keynes.

Remark

In-text example
Author and Author (year) ...

Moerman and Lorenzen (2016)

Reference list example
Author, A., & Author, B. (year). Title of chapter. In E. Editor (Ed.), Book title in italics. (pp. xx). Publisher.

Moerman, F., & Lorenzen, K. (2016). Hygienic design of open food processing equipment. In S. Kennedy (Ed.), Food
      Protection and Security: Preventing and Mitigating Contamination during Food Processing and Production.
      (pp. 101‑166). Elsevier.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
(Author et al., year)

(Hoffmann et al., 2016)

Reference list example
Author, A., Author, B., Author, C., Author, D., Author, E., Author, F., & Author, G. (year). Title of chapter. In E. E. Editor
      & F. F. Editor (Eds.), Book title in italics. (pp. xx). Publisher.

Hoffmann, M., Haselbauer, K., Haberl, A., Blab, R., Simoner, M. Dieplinger, K. & Hartl, T. (2016). A new asset
      management approach for inland waterways. In J.‑M. Torrenti & F. La Torre (Eds.), Materials and Infrastructures
      2. (pp. 131‑145). Blackwell.

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
(Organisation [Abbreviation], year) ...

(Norwegian Environmental Agency [NEA], 2013)

Reference list example
Organisation. (year). Title of brochure in italics [Brochure]. https://xxxxx

Norwegian Environmental Agency. (2013). Right to roam [Brochure].
      https://www.miljodirektoratet.no/globalassets/publikasjoner/M86/M86.pdf

Remark
1. When author and publisher are the same, omit the publisher name.
2. The name of an organization is fully spelled in the first in-text citation, in the following citations an abbreviation is used: Abbreviation (year) ....

In-text example
Author (year) ...

Van der Meer-Ler (2011) suggests ...

Reference list example
Author, A. A. (year). Title of brochure in italics [Brochure]. Publisher. https://xxxxx

Van der Meer‑Ler, L. A. (2011). Advanced course environmental biotechnology [Brochure]. BioTech Delft. 
      http://www.bodl.bt.tudelft.nl/content/documents/Brochure_EB_2011.pdf

Remark
Additional information that is important for identification and retrieval, place a description of the contents in brackets following the title: [Brochure].

In-text example
.... "title of the lecture note" (year) ...

The TU Delft lecture note "Wastewater treatment" (2011) reports that ...

Reference list example
Organisation. (year). Title of lecture note in italics (Vol. xx). https://xxxxx

Technical University Delft. (2011). W1 ‑ Wastewater treatment; SANITARY ENGINEERING ‑ CT3420 (Vol. 2011). 
       https://blackboard.tudelft.nl/bbcswebdav/courses/12860‑091003‑ocw/Readings_public/WastwaterTreatmen
       t_2011_Ch1‑7.pdf 

Remark
1. When author and publisher are the same, omit the publisher name.
2. The name of an organization is fully spelled in the first in-text citation, in the following citations an abbreviation is used: Abbreviation (year) ....

In-text example
Author (2007) ...

Van Meurs (2007)

Reference list example
Author, A. (year). Title of lecture note in italics. Publisher.

Van Meurs, G. (2007). Environmental geotechnics AES1640. TU Delft.

Remark

In-text example
Author and Author (year) ...

Prins and Koolwijk (2004)

Reference list example
Author, A., & Author, B. B. B. (year). Title of lecture note in italics. Publisher.

Prins, M., & Koolwijk, J. S. J. (2004). Architectural practice BK AR0520. TU Delft.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
Author et al. (year, p. xx) ...

Jonkman et al. (2015, p. 66)

Reference list example
Author, A. A., Author, B. B. B. B., Author, C., Author, D. D. D. D., & Author, E. E. (year). Title of lecture note in italics.
      Publisher.

Jonkman, S. N., Steenbergen, R. D. J. M., Morales‑Napoles, O., Vrouwenvelder, A. C. W. M., & Vrijling, J. K. (2015).
      Probabilistic design: Risk and reliability analysis in civil engineering CIE4130. TU Delft.

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
(Author, year) ...

(Cutler, 2011)

Reference list example
Author, A. A. (year). Title of article. Title of periodical in italics, volume number(issue number), pp‑pp.

Cutler, A. D. (2011). High‑frequency pulsed combustion actuator experiments. AIAA Journal, 49(9), 1943‑1950.

Remark
Include the issue number if the journal is paginated by issue.

In-text example
(Author & Author, year, p. xx) ...

(Al Aukidy & Verlicchi, 2017, p. 486) ...

Reference list example
Author, A., & Author, B. (year). Title of article. Title of periodical in italics, volume number, pp‑pp.

Al Aukidy, M., & Verlicchi, P. (2017). Contributions of combined sewer overflows and treated effluents to the bacterial
      load released into a coastal area. Science of the Total Environment, 607‑608, 483‑496.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
Author et al. (year, p. xx) ...

Xu et al. (2017, p. 298) ...

Reference list example
Author, A., Author, B., Author, C., Author, D., Author, F., Author, G., Author, H., & Author, I. (year). Title of article. Title of
      periodical in italics, volume number, pp‑pp.

M., Wang, G., Zeng, Z., Chen, J., Zhang, X., Wang, L., Song, W., & Xue, Q. (2017). Diverse wettability of
      superoleophilicity and superoleophobicity for oil spill cleanup and recycling. Applied Surface Science,
      426, 1158‑1166

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
("First words title of article," year)

("Research Central, " 2017)

Reference list example
Title of article. (year). Title of periodical. Publisher.

Research central: Examining ethnic disparities within the juvenile justice system. (2017, May/June). OJJDP News @
      a Glance. OJJDP.

Remark
1. When a work has no identified author, the in-text citation contains the first few words of the title (use double quotation marks) and the publication year.
2. Only when the author of a work is desginated as "Anonymous", "Anonymous" takes the place of the author name.

In-text example
(Author, year) ...

(Gikas, 2016)

Reference list example
Author, A. A. (year). Title of article. Title of periodical in italics, volume number(issue number),
      pp‑pp. https://doi.org/xxxxx

Gikas, G. D. (2016). Water quantity and hydrochemical quality monitoring of Laspias River, North Greece. Journal of
      Environmental Science and Health ‑ Part A Toxic/Hazardous Substances and Environmental Engineering, 52(14),
      1312‑1321. https://doi.org/10.1080/10934529.2017.1357408 

Remark
1. For journal articles without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed journal article.
2. For journal articles without DOIs from websites, use a URL in the reference.

In-text example
... (Author & Author, year) ...

It has been stated (Bouthoorn & Erkel, 2011)

Reference list example
Author, A. A., & Author, B. B. (year). Title of article. Title of periodical in italics, volume number(issue number),
      pp‑pp. https://doi.org/xxxxx

Bouthoorn, S. H., & Erkel, N. E. (2011). Alcohol intoxication among Dutch adolescents: Acute medical complications in
      the years 2000‑2010. Clinical Pediatrics, 50(3), 244‑251. https://doi.org/10.1177/0009922810388509 

Remark
1. Use the ampersand only in the parenthetical format of the in-text citation.
2. For journal articles without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed journal article.
3. For journal articles without DOIs from websites, use a URL in the reference.

In-text example
(Author et al., year) ...

(Chamoun et al., 2017)

Reference list example
Author, A., Author, B., & Author, C. C. (year). Title of article. Title of periodical in italics, volume number,
      pp‑pp. https://doi.org/xxxxx

Chamoun, S., De Cesare, G., & Schleiss, A. J. (2017). Management of turbidity current venting in reservoirs under
      different bed slopes. Journal of Environmental Management, 204, 519‑530. https://doi.org/10.1016/j.jenvman.
      2017.09.030​​​​​​​ 

Remark
​​​​​​​1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.
3. For journal articles without DOIs from most academic research databases (e.g. Google Scholar, Scopus, Web of Science), do not include a URL because these works are widely available. The reference should be the same as the reference for a printed journal article.
4. For journal articles without DOIs from websites, use a URL in the reference.

In-text example
Author (year) ...

Ficker (2017)

Reference list example
Author, A. (year). Title of article. Title of proceedings in italics, volume number. https://doi.org/xxxxx 

Ficker, T. (2017). Rupture strength and irregularity of fracture surfaces. IOP Conference series: materials science and
      engineering, 245. https://doi.org/10.1088/1757‑899X/245/3/032009 

Remark
Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
Author and Author (year) ...

Kaas and Lent (2011) published their ...

Reference list example
Author, A. A., & Author, B. (year). Title of article. Title of proceedings in italics, volume number, pp‑pp.
      https://doi.org/xxxxx 

Kaas, J. H., & Lent, R. (2011). The basic non uniformity of the cerebral cortex. Proceedings of the National Academy of
      Sciences, 105, 12593‑12598. https://doi.org/10.1073/pnas.0805417105 

Remark
1. Use the ampersand only in the parenthetical format of the in-text citation.
2. Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
Author, Author, Author, and Author (year, p. xx) ...

Meesawasd, Boonyasiriwat, Kongnuan and Chamchod (2016, p. 387) ...

Reference list example
Author, A., Author, B., Author, C., & Author, D. (year). Title of article. Title of proceedings in italics, volume number,
      pp‑pp. https://doi.org/xxxxx 

Meesawasd, N., Boonyasiriwat, C. , Kongnuan, S., & Chamchod, F. (2016). Finite element modeling for stress analysis
      of a buried pipeline under soil and traffic loads. IEEE International Conference on Industrial Engineering
      and Engineering Management, 2016, 385‑390. https://doi.org/10.1109/IEEM.2016.7797902​​​​​​​ 

Remark
​​​​​​​1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.
3. Include a DOI for all works that have a DOI, regardless which version you used: online or printed.

In-text example
... (Organisation [Abbreviation], year) ...

..... resulted in choosing the points for action (Nationale Raad voor Landbouwkundig Onderzoek [NLRO], 1999).

Reference list example
Organisation. (year). Title of work in italics (Report title and report number). 

Nationale Raad voor Landbouwkundig Onderzoek. (1999). Nanotechnologie: speerpunten voor actie
      (NRLO‑rapport Vol. 99/7).

Remark
The name of an organization is fully spelled in the first in-text citation, in the following citations an abbreviation is used: Abbreviation (year) ....

In-text example
Author (year) ...

Amiro (1992) ...

Reference list example
Author, A. A. (year). Title of work in italics (Report title and report number). Publisher.

Amiro, B. D. (1992). Atmospheric submodel for the assessment of Canada's nuclear fule waste management concept
      (AECL Report Issue 9889). Atomic Energy of Canada.

Remark

In-text example
(Author & Author, year) ...

(Kendy & Bradbury, 1988)

Reference list example
Author, A., & Author, B. B. (year). Title of work in italics (Report title and report number). Publisher.

Kendy, E., & Bradbury, K. R. (1988). Hydrogeology of the Wisconsin River valley in Marathon County, Wisconsin
      (Information Circular Wisconsin Geological and Natural History Survey Issue 64). University of Wisconsin.

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
Author et al. (year) ...

Evans et al. (1989)

Reference list example
Author, A. A., Author, B. B., & Author, C. C. (year). Title of work in italics (Report title and report number). Publisher.

Evans, R. O., Gilliam, J. W., and Skaggs, R. W. (1989). Effects of agricultural water table management on drainage
      water quality (Report Water Resources Research Institute of The University of North Carolina Issue 237).
      North Carolina State University.

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.

In-text example
Organisation (Abbreviation, year) ...

De Nationale Raad voor Landbouwkundig Onderzoek (NRLO, 1996) ...

Reference list example
Organisation (year). Title of work in italics (Report title and report number). Publisher. https://xxxxx 

Nationale Raad voor Landbouwkundig Onderzoek. (1996). De milieubewuste consument (NRLO‑rapport Vol. 96/6).
      Innovatie Agro & Natuur. http://publications.tno.nl/publication/34616177/kY2Bz5/NRLO‑1996‑06.pdf 

Remark
1. When author and publisher are the same, omit the publisher name.
2. The name of an organization is fully spelled in the first in-text citation, in the following citations an abbreviation is used: Abbreviation (year) ....

In-text example
Author (year) ...

Sugden (2014)

Reference list example
Author, A. (year). Title of work in italics (Report title and report number). Publisher. https://xxxxx 

Sugden, F. (2014). Landlordism, tenants and the groundwater sector: Lessons from Tarai‑Madhesh, Nepal
      (IWMI Research Report 162). International Water Management Institute. http://www.iwmi.cgiar.org/Publications
      /IWMI_Research_Reports/PDF/pub162/rr162.pdf 

In-text example
... Author and Author (year) ...

It is stated by Van der Wel and Bergen (2000) ...

Reference list example
Author, A., & Author, B. B. B. (year). Title of work in italics (Report title and report number). Publisher. https://xxxxx 

Van der Wel, N., & Bergen, V. H. S. (2000). Plattelandsvernieuwing en cultuur: Interactieve planontwikkeling
      (NRLO‑rapport nr. 2000/8). Innovatie Agro & Natuur. http://publications.tno.nl/publication/34614835/
      QuPGHi/NRLO‑2000‑08.pdf 

Remark
Use the ampersand only in the parenthetical format of the in-text citation.

In-text example
(Author et al., year) ...

(Wassenaar et al., 2017)

Reference list example
Author, A. A. A., Author, B., Author, C. C. C., & Author, D. D. D. (year). Title of work in italics (Report
      title and report number). Publisher. https://xxxxx 

Wassenaar, P. N. H., Janssen, N., De Poorter, L. R. M., & Bodar, C. W. M. (2017). Substances of very high concern
      and the transition to a circular economy : An initial inventory (RIVM report 2017‑0071). RIVM. http://www.rivm.nl/
      bibliotheek/rapporten/2017‑0071.html 

Remark
1. When a reference has up to twenty authors, spell out all authors' names in the reference list. Twenty-one or more authors: only mention the first nineteen authors, followed by an omission sign . . . the last author.
2. For a work with three or more authors, include only the name of the first author plus "et al." in every citation.