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3. Journal of the Acoustical Society of America;Greenspon;Vibrations of cross stiffened and sandwich plates with applications to underwater sound radiators,1961
4. U.S. Air Force Flight Dynamics Laboratory, AFFDL-TR-69-84;Schimke;Approximate solution of plane orthotropic elasticity problems,1970
5. Acta technica CSAV;Sobotka;Vibrations of rectangular orthotropic viscoelastic plates,1969