D-Olier,第7页 D'Olier, Franklin, The Secondary Campaigns, United States Strategic Bombing Survey, Summary Report (European War): 12, September 30, 1945 [March 23, 2020], (原始内容存档于2013-11-05) –通过Hyperwar Foundation
D-Olier,第7页 D'Olier, Franklin, The Secondary Campaigns, United States Strategic Bombing Survey, Summary Report (European War): 12, September 30, 1945 [March 23, 2020], (原始内容存档于2013-11-05) –通过Hyperwar Foundation