Young, Warren C. creator text New York McGraw-Hill 1989 6th ed. monographic 763p. ; 624.1760212YOU http://books.google.com.pk/books/about/Roark_s_Formulas_for_Stress_and_Strain.html?id=pummClLoFXEC&redir_esc=y http://books.google.com.pk/books/about/Roark_s_Formulas_for_Stress_and_Strain.html?id=pummClLoFXEC&redir_esc=y