Beer, F. P. P., Johnston, E. R. R., DeWolf, J. T., & Johnston, E. R. Mechanics of materials /Ferdinand P. Beer, E. Russell Johnston, Jr., John T. DeWolf. McGraw-Hill Higher Education.

Beer, Ferdinand P.(Ferdinand Pierre),1915-2003., E. Russell(Elwood Russell),1925-2010 Johnston, John T. DeWolf, và E. Russell  Johnston. Mechanics of Materials /Ferdinand P. Beer, E. Russell Johnston, Jr., John T. DeWolf. McGraw-Hill Higher Education.

Beer, Ferdinand P.(Ferdinand Pierre),1915-2003., E. Russell(Elwood Russell),1925-2010 Johnston, John T. DeWolf, và E. Russell  Johnston. Mechanics of Materials /Ferdinand P. Beer, E. Russell Johnston, Jr., John T. DeWolf. McGraw-Hill Higher Education.