Give the complete DOI if the article has one; if there is no DOI, give the URL for the article. (The complete DOI consists of the prefix https://doi.org followed by the DOI identifier or locator found in the source.)
For unpaginated online articles, you may include in your note a locator, such as a numbered paragraph or a heading from the article.
Note on breaking URLs and DOIs
If you must break a URL or a DOI at the end of a line, break it after a colon or a double slash or before any other mark of punctuation.