The superb Finnish aviation history journal Suomen ilmailuhistoriallinen lehti will be publishing shortly a new special issue on the pre-war fighter acquisition programme of the FAF:
http://www.saunalahti.fi/myma1/erikois2/erikois2.html
48 pages in A4 format, softcover, in Finnish. Written by Jukka Raunio, an aircraft designer by trade. All of his books are excellent and are excellent purchases for aircraft enthusiasts, less so for paint enthusiasts...