Speech to the Cambridge University Aeronautical Society, April 1925 in Trenchard, Man of Vision (1962) p. 519
Хью Тренчард, 1-й виконт Тренчард: Цитаты на английском языке
Given by Trenchard in 1946. As listed on Skygod.com - Great Aviation Quotes http://www.skygod.com/quotes/airpower.html