Harvard University's Suggested Film Viewing List Non-Fiction Films - (120): (2012)
This list is "an educational resource that offers guidance and encouragement as students seek to find points of orientation within the vast history of film and video." It is not a list of the best films of all time. Rather, it reflects a variety of criteria.
Source: https://ves.fas.harvard.edu/files/ves/files/fvs_suggested_viewing_2012.pdf