Não informado. (1930). Engineering and mining world. McGraw-Hill Publications.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Engineering and Mining World. New York: McGraw-Hill Publications, 1930.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Engineering and Mining World. McGraw-Hill Publications, 1930.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.