"Include a DOI for all works that have a DOI, regardless of whether you used the online version or the print version."
"The preferred format of the DOI has changed over time; although older works use previous formats (e.g., "http://dx.doi.org/" or "doi:" or "DOI:" before the DOI number), in your reference list, standardize DOIs into the current preferred format for all entries": https://doi.org/<DOI number>.
Examples:
Convert DOI: 10.1017/S0008423910000983 into https://doi.org/10.1017/S0008423910000983.
Convert http://dx.doi.org/10.1037/a0040251 into https://doi.org/10.1037/a0040251.
"If an online work has both a DOI and a URL, include only the DOI."
Example:
Bushnik, T., Tjepkema, M., & Martel, L. (2020). Socioeconomic disparities in life and health expectancy among the household population in Canada. Health Reports, 31(1), Jan. 2020, pp. 3–14. https://www.doi.org/10.25318/82-003-x202000100001-eng
Narrative citation: Bushnik et al. (2020)
Parenthetical citation: (Bushnik et al., 2020)
"For works without DOIs from websites . . . provide a URL in the reference (as long as the URL will work for readers)."
Example:
Health Canada. (2020). The health impacts of air pollution in Canada. http://publications.gc.ca/pub?id=9.887335&sl=0
Narrative citation: Health Canada (2020)
Parenthetical citation: (Health Canada, 2020)
"For works without DOIs from most academic research databases, do not include a URL or database information."
Example:
Claxton, N. X., & Price, J. (2019). Whose land is it? Rethinking sovereignty in British Columbia. BC Studies, 204, 115–138.
Narrative citation: Claxton and Price (2019)
Parenthetical citation: (Claxton & Price, 2019)
Include the URL for a work from a database that includes works of limited circulation or original, proprietary content. If the URL requires a login, provide the URL of the home page or login page of the database instead of the URL for the work.
Example:
Palser, S., Smith, S., Nash, E. F., Agarwal, A., & Smyth, A. R. (2019). Treatments for preventing recurrence of infection with Pseudomonas aeruginosa in people with cystic fibrosis. Cochrane Database of Systematic Reviews. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=reference&D=coch&NEWS=N&AN=00075320-100000000-10711
Narrative citation: Palser et al. (2019)
Parenthetical citation: (Palser et al., 2019)
(Publication Manual of the American Psychological Association, 2020, pp. 299–300)