Example annotated bibliography: 
(Example from Miranda Flores, California State University Northridge, accessed https://libguides.csun.edu/research-strategies/annotated-bibliography. Annotations added for clarity.)
Other useful resources for annotated bibliographies:
OWL Purdue Annotated Bibliography
Cornell University: How to Prepare an Annotated Bibliography
University of Nevada, Reno: APA Citation Guide (7th Edition): Annotated Bibliography