No Edition Remarks. 50 pages. BIOS Final Report No 1339 Item No. 25. German Aircraft Heat Exchanger Equipment. Paperback book with blue cover. Library stamp to front cover. Pages are mostly clean overall, with moderate tanning throughout. Staple binding is firm with noticeable rust. Text is unaffected. Paper covers have mild edge wear with creasing & scuffing. Visible sunning to spine. Rust marks to covers.