The other day I was randomly browsing some book on the shelf at the office I work in, when I happened upon this title:
IL LIBRO DEL FAI, edited by Renato Bazzoni & Marco Magnifico (1990 by Electra, Milano)
UPC: 9 788843 533459
The book (in both Italian & English) appears to be a sort of compendium of the various properties owned, or at least under the care of FAI (Fondo per l'Ambiente Italiano, a private non-profit foundation).
Anyway, I was quite surprised to find that Via Del Balbianello has it's own chapter near the end of the book. I've scanned the relative pages, combined them into a PDF, zipped it, and uploaded it to sendspace.com:
The file is just over 10mb and I think will only be active for 30 days, so... get it while you can.