YOUNG, W. C. (1989). Roark's Formulas For Stress & Strain. McGraw-Hill.
Lua i Stíl Chicago (17ú heag.)YOUNG, Warren C. Roark's Formulas For Stress & Strain. McGraw-Hill, 1989.
Lua MLA (8ú heag.)YOUNG, Warren C. Roark's Formulas For Stress & Strain. McGraw-Hill, 1989.
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