Thực đơn
Douglas_O-31 Biến thểDữ liệu từ: "U.S. Army Aircraft 1908-1946" by James C. Fahey, 1946, 64pp.
XO-31YO-31YO-31AYO-31BYO-31CY1O-31CThực đơn
Douglas_O-31 Biến thểLiên quan
Douglas MacArthur Douglas Costa Douglas A-4 Skyhawk Douglas A-26 Invader Douglas A-1 Skyraider Douglas A-3 Skywarrior Douglas DC-3 Douglas Aircraft Company Douglas A-20 Havoc Douglas EngelbartTài liệu tham khảo
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