Bruce Posner's Introduction to Unseen Cinema can be read on-line. Posner argues against the European-art centric model for the appearance of an art-as-cinema, presenting his Unseen Cinema programs as the proof for the argument he makes in this article.
Marcin Gizycki has a nice history of the development of avant-garde film in Poland. "There was no organized avant-garde film movement in Poland before WW2, which does not mean that there were no avant-garde films made. This paradox is easily explained. A number of artists more or less connected with avant-garde circles worked separately on films or film-related projects...."