Kehl, G. L. (1949). The principles of metallographic laboratory practice (3rd ed.). McGraw-Hill.
Dyfyniad Arddull ChicagoKehl, George Louis. The Principles of Metallographic Laboratory Practice. 3rd ed. New York: McGraw-Hill, 1949.
Dyfyniad MLAKehl, George Louis. The Principles of Metallographic Laboratory Practice. 3rd ed. McGraw-Hill, 1949.
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