Não informado. (1942). Machine tools. National Machine Tool Builders Association.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Machine Tools. Cleveland, Ohio: National Machine Tool Builders Association, 1942.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Machine Tools. National Machine Tool Builders Association, 1942.
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