Hobbs, G. M. (1972). Practical mathematics (3rd.ed.). American technical.
Chicago-čujuhus (17. p.)Hobbs, Glen M. Practical Mathematics. 3rd.ed. Illinois: American technical, 1972.
MLA-čujuhus (9. p.)Hobbs, Glen M. Practical Mathematics. 3rd.ed. American technical, 1972.
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