APA's Publication Manual, 7th Edition, provides complete style guidelines and should be consulted first in all matters concerning APA Style (Bernhard Library BF 76.7 .P83 2020). In lieu of the paper copy the APA Manual the online APA Style blog very helpful.
APA 7th Style and Grammar Guidelines
The style and grammar guidelines pages present information about APA Style as described in the Publication Manual of the American Psychological Association, Seventh Edition. Excellent resource for overview and link to references, in-text citations and formatting.