Not too many books and other sources of information on italian prog, especially for non-italian language readers.

Here are some of my main sources of information, starting with the italian ones:

ENCYCLOPEDIAS AND DISCOGRAPHIES

ESSAYS AND STUDIES

BEAT, SIXTIES, EIGHTIES

MUSIC IN THE CITIES

GROUPS AND ARTISTS OF THE ITALIAN PROGRESSIVE

 

here's a couple of english written books on the subject:

 

and a japanese one, containing black & white pictures of all the records described, but difficult to understand for non-japanese readers: