Multiple Viewpoints

I am not sure if Picasso's convention of multiple views is particularily distinct from orthographic projection. He renders a frontal view of one eye, the other in profile, and the mouth in the opposite profile.  But if we accept engineering drawings as legal documents, then we have to accept Picasso as an accurate portrayer of the human form. After all, we have no trouble assimilating all these views into a recognisable face; we can even identify the model.

Pablo Picasso, 3.6.1939 reproduced in David Douglas Duncan; p. 130

Pablo Picasso 4.12.1937, reproduced in David Douglas Duncan;
Picasso's Picassos, New York, Ballantine, 1968, p. 106