Hi. For example, Aircraft Profile 242 "IK Fighters 1930-40s" by Sime I Ostric and Cedomir J. Janic devoted to Ikarus factory.
Also there is very good book by Zlatomir Grujih "Aviacia Srbie i Jugoslavie 1901-1994", 1997 (srpsk language, especially 2nd chapter p.p.65-106)
Of course, Jane's encyclopaedia and some Jane's all the world's aircraft (for example, Jane's AWA 1938, p.313c, look this page on the link)
http://rapidshare.com/files/110567387/P313.jpg.html
Best regards,