Não informado. (1920). Contractors and engineers monthly. Buttenheim-Dix Publishing.
Chicago-viite (17. p.)Não informado. Contractors and Engineers Monthly. New York: Buttenheim-Dix Publishing, 1920.
MLA-viite (8. p.)Não informado. Contractors and Engineers Monthly. Buttenheim-Dix Publishing, 1920.
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