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2) E. L. Wilson.: “Solid SAP”, Structural Eng. Lab. Univ. Calif., Berkeley (1972)
3) K. K. Guputa.: “Solution of Eigenvalue Problems by Sturm Sequence Method”, Int. J. for Numerical Method for Eng. Vol.4., pp.379-404 (1972)
4) S. Okamoto.: “Aseismatic Engineering”, OHM Book Co.,(in Japanese), pp.371-401 (1972)
5) J. Petrovski., T. Paskalov., D. Jurukovski.: “Dynamic Full-Scale Test of an Earth Fill Dam”, Geotechnique., 24 (2) pp.193-206 (1974)