Optimized Calculation of Natural Frequencies of Rectangular Plates by Ritz's Method and Experimental Verification by Laser Interferometry - Francisco J. Nieves Pavón; Francisco Gascón Latasa; BAYON ROJO, ANA ISABEL (Optimized Calculation Of Natural Frequencies Of Rectangualar Plates By Ritz's Method And Experimental Verification By Laser Interferometry, 2008)