Watkinson, J. (2004). Art of the helicopter. Elsevier Butterworth-Heinemann.
Lua i Stíl Chicago (17ú heag.)Watkinson, John. Art of the Helicopter. Oxford ; Burlington, MA: Elsevier Butterworth-Heinemann, 2004.
Lua MLA (9ú heag.)Watkinson, John. Art of the Helicopter. Elsevier Butterworth-Heinemann, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.