To Kill a Mockingbird on IMDB
https://www.imdb.com/title/tt0056592/?ref_=nv_sr_1
Comprehensive entry for To Kill a Mockingbird on the Internet Movie Database
To Kill a Mockingbird on Rotten Tomatoes
https://www.rottentomatoes.com/m/to_kill_a_mockingbird/
Overview of critical reception of To Kill a Mockingbird on Rotten Tomatoes
About Robert Mulligan
https://www.britannica.com/biography/Robert-Mulligan
A biography of Robert Mulligan, the director of To Kill a Mockingbird