Não informado. (1920). Contractors and engineers monthly. Buttenheim-Dix Publishing.
Chicago-Zitierstil (17. Ausg.)Não informado. Contractors and Engineers Monthly. New York: Buttenheim-Dix Publishing, 1920.
MLA-Zitierstil (8. Ausg.)Não informado. Contractors and Engineers Monthly. Buttenheim-Dix Publishing, 1920.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.