Place of publication is required for books and monographs, not articles.
The place of publication is the "name of the city where the publisher is located". The place can be found on the title page or verso of the title page. Use the first city listed or the one most familiar to the audience.
Follow the city name with two-letter abbreviation for the state, as Chicago (IL).
Follow city names from other countries with the ISO country code, as London (GB), OR use the name of the country as it appears in the publication, as London (England).
Treat each occurrence of a city the same in the end reference list.
Exception: If a newspaper title does not contain the name of the location where it is published, add the location in parenthesis within or after the title.