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 J. S. Tomar and A. K. Gupta, “Effect of Thermal Gradient on Frequencies of Orthotropic Rectangular Plate Whose Thickness Varies in Two Directions,” Journal ofSound and Vibration, Vol. 98, No. 2, 1985, pp. 257- 262.
 J. S. Tomar and A. K. Gupta, “Effect of Exponential Temperature Variation on Frequencies of an Orthotropic Rectangular Plate of Exponentially Varying Thickness,” Proceeding of the Workshop on Computer Application in Continum Mechanics, Roorkee, 11-13 March 1986, pp. 183-188.
 U. S. Gupta, R. Lal and S. Sharma, “Vibration Analysis of Non-Homogenous Circular Plate of Nonlinear Thickness Variation by Differential Quadrature Method,” Journal of Sound and Vibration, Vol. 298, No. 4-5, 2006, pp. 892-906.
 A. K. Gupta, T. Johri and R. P. Vats, “Thermal Effect on Vibration of Non-Homogeneous Orthotropic Rectangular Plate Having Bi-Directional Parabolically Varying Thickness,” Proceeding of International Conference in World Congress on Engineering and Computer Science 2007 (WCECS 2007), San Francisco, 24-26 October 2007, pp. 784-787.
 A. K. Gupta, A. Kumar and D. V. Gupta, “Vibration of Visco-Elastic Orthotropic Parallelogram Plate with Linearly Thickness Variation,” Proceeding of International Conference in World Congress on Engineering and Computer Science 2007 (WCECS 2007), San Francisco, 24-26 October 2007, pp. 800-803.
 A. K. Gupta, A. Khanna and D. V. Gupta, “Free Vibration of Clamped Visco-Elastic Rectangular Plate Having Bi-Directional Exponentially Thickness Variations,” Journal of Theotrocial and Applied Mechanics, Vol. 47, No. 2, 2009, pp. 457-471.
 A. K. Gupta, N. Aggarwal, D. V. Gupta, S. Kumar and P. Sharma, “Study of Non-Homogeneity on Free Vibration of Orthotropic Visco-Elastic Rectangular Plate of Parabolic Varying Thickness,” Advanced Studies of Theory Physics, Vol. 4, No. 10, 2010, pp. 467-486.
 K. Bhasker and B. Kaushik, “Simple and Exact Series Solutions for Flexure of Orthotropic Rectangular Plates with Any Combination of Clamped and Simply Supported Edges,” Composite Structure, Vol. 63, No. 1, 2004, pp. 63-81.