Vaclav Nemecek, "Reconnaissance Aircraft and Light Bombers," chap. 24 of The History of Societ Aircraft from 1918 (Willow Books, 1986), pp.186-200, 422-423. English language book (photocopied excerpt).
No restrictions on access.
Russian Aeronautical Collection, ACC. 2006-0034, National Air and Space Museum, Smithsonian Institution.