Butts, A. (1943). Metallurgical problems (2a. ed.). Robert E. Krieger.
Chicago-čujuhus (17. p.)Butts, Allison. Metallurgical Problems. 2a. ed. Nueva York: Robert E. Krieger, 1943.
MLA-čujuhus (9. p.)Butts, Allison. Metallurgical Problems. 2a. ed. Robert E. Krieger, 1943.
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