J. Alexander, "The Russian Aces," in Bruce Robertson (ed.), -- Air Aces of the 1914-1918 War -- (Fallbrook (CA) : Aero Publishers, 1964). (photocopy; 2 copies)
"The Aces - Russian," from -- An Illustrated History of World War One -- (http://www.wwiaviationcom/aces/aces_russian.shtml), printed August 12, 2003.
"Russian Aces of WW1 - Alexander Kozakov," from -- An Illustrated History of World War One -- (http://www.wwiaviationcom/aces/aces/ace_Kozakov.shtml), printed August 12, 2003.
"Famous Russian pilots," from -- Air Space museums, launch complex, sites -- (http://www.armymuseum.ru/airspace.history5.html), printed August 12, 2003.
No restrictions on access.
Russian Aeronautical Collection, ACC. 2006-0034, National Air and Space Museum, Smithsonian Institution.