Unknown creator; St. Louis University; Parks College of Saint Louis University. (1941). Parks College industrial machine shop.
Παραπομπή σε μορφή Chicago (17η εκδ.)Unknown creator; St. Louis University; Parks College of Saint Louis University. Parks College Industrial Machine Shop. 1941.
Παραπομπή σε μορφή MLA (8th εκδ.)Unknown creator; St. Louis University; Parks College of Saint Louis University. Parks College Industrial Machine Shop. 1941.
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