Howard's Whirlybirds : Howard Hughes' Amazing Pioneering Helicopter Exploits
Donald J. Porter | angielski | twarda oprawa | 240 str. | 2013
Hughes HK-1 (H-4) Flying Boat Manual
U.S. War Department | angielski | miękka oprawa | 170 str. | 2009
AH-64 Apache
Christian Rastätter | niemiecki | twarda oprawa | 224 str. | 2021
AH-64 Apache Attack Helicopter
Headquarters Department of the Army | angielski | miękka oprawa | 656 str. | 2011
The Apache in European Service
Darren Willmin | angielski | miękka oprawa | 96 str. | 2016