Q. What is a volume/issue number?

APA 6th Edition

When writing a reference to a periodical (e.g., journal article), volume and issue numbers are standard elements. The difference between the numbers is that "volume typically refers to the number of years the publication has been circulated, and issue refers to how many times that periodical has been published during that year" (Wikipedia, n.d., para. 2).

For example, in the reference below, the volume number is 49 and the issue number is 4:

Godfrey, D. (2005). Adapting historical citations to APA Style. Journal of Broadcasting & Electronic Media, 49(4), 544-547. https://doi.org/10.1207/s15506878jobem4904_15

Provide the journal issue number in the reference if each issue starts the page numbering at 1 (American Psychological Association, 2010, p. 198). Please see "Got Volume?" in the APA Style Blog for approaches to creating a reference when the volume number is missing.

References

American Psychological Association. (2010). Publication manual of the American Psychological Association (6th ed.). Washington, DC: Author. 

Periodical literature. (n.d.). In Wikipedia. Retrieved January 3, 2019, from https://en.wikipedia.org/wiki/Periodical_literature

APA 7th Edition

When creating a reference to a periodical, such as a journal article, volume and issue numbers are standard elements. The difference between the numbers is that "volume typically refers to the number of years the publication has been circulated, and issue refers to how many times that periodical has been published during that year" (Wikipedia, n.d., para. 2).

Volume numbers in references should be italicized (American Psychological Association [APA], 2020, p. 294), but "do not italicize the issue number, the parentheses, or the comma after the issue number" (APA, 2020, p. 294).

In the reference below, the volume number is 49 and the issue number is 4:

Godfrey, D. (2005). Adapting historical citations to APA Style. Journal of Broadcasting & Electronic Media, 49(4), 544-547. https://doi.org/10.1207/s15506878jobem4904_15

If a resource doesn't have a volume or issue number, omit that information from the reference (APA, 2020, p. 294).

Reference

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org/10.1037/0000165-000