Important examples are to be found in the Vollard Suite, the 100 etchings creasted by him between 1930-1937 where he portrays himself as a man-beast - a minotaur
I don't think there are any works where his image is in dispute (he certainly does not insert himself into Guernica, or Les Demoiselles d'Avignon - so don't go looking!)
I have studied Picasso fairly extensively, and can think of no other examples, outside his self-portraits and the Vollard group.