STRUCTURE OF JOURNAL ARTICLE CITATIONS
Journal article citations include the following elements: author(s) name(s), article title, journal title, volume number, issue number, a hyphenated span of page numbers, and (if possible), a Digital Object Identifier (DOI). On DOIs, see the tab on this page that explains them.
JOURNAL VOLUME AND ISSUE NUMBERS
When you create the reference-list entry for a journal article, you have to put the volume number after the title of the journal. Both the title and the volume number go in italics. Sometimes there is no issue number. In the following example, the volume number is 59:
Lopez, B. (2018). How to cite using APA. Journal of Citation, 59, 39-41.
Sometimes journals use issue numbers in addition to volume numbers. Issue numbers are put in parentheses after the volume numbers, with no space in between and without italics. (Some journals don’t use issue numbers, so if your source does not have an issue number, you do not need one in your reference entry, as in the previous example, above.) In the following reference-list example, the issue number is 2:
Lopez, B. (2018). How to cite using APA. Journal of Citation, 59(2), 39-41.
For journal articles, APA style asks you to include a Digital Object Identifier (DOI) at the end of a citation, if one is available. The purpose of DOIs is to make sources permanently locatable online. DOIs should begin with the prefix https://doi.org/. To find a DOI for an article, go to www.crossref.org and copy-and-paste the citation information into the search box for Metadata. Here's an example of a journal article citation with a DOI:
McCauley, S. M., & Christiansen, M. H. (2019). Language learning as language use: A cross-linguistic model of child language development. Psychological Review, 126(1), 1-51. https://doi.org/10.1037/rev0000126