Roberts, G. A., & Cary, R. A. (1980). Tool steels. American society for metals.
Dyfyniad Arddull ChicagoRoberts, George A., and Robert A. Cary. Tool Steels. Ohio: American society for metals, 1980.
Dyfyniad MLARoberts, George A., and Robert A. Cary. Tool Steels. American society for metals, 1980.
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