Fullformexpand.com, 2026. "XB-42." Accessed April 25, 2026. https://www.fullformexpand.com/xb-42/experimental-b-42-mixmaster-twin-engined-bomber.
"XB-42." (n.d.). Fullformexpand.com. Retrieved April 25, 2026, from https://www.fullformexpand.com/xb-42/experimental-b-42-mixmaster-twin-engined-bomber.
XB-42. (2026). Fullformexpand.com. Available at: https://www.fullformexpand.com/xb-42/experimental-b-42-mixmaster-twin-engined-bomber (Accessed: 25 April 2026).