green gate

radio-craft: 50 years of radio by hugo gernsback

collector's guide to toy sewing machines

radio manufacturers of the 1920's volume 2: freed-eisemann to priess by alan douglas

radio manufacturers of the 1920's volume 1: a-c dayton to j.b. ferguson, inc. by alan douglas

radio tubes & boxes of the 1920's by george fathauer

classic cones (radio cone speakers) by buford & jane chidester

the collector's vacuum tube handbook by robert millard

cathedral & tombstone radios by mark stein

the compleat talking machine, 5th ed (antique phonographs) by eric reiss