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2. V. E. Shamanskii, Numerical Solution of Problems of Groundwater Flow Problems on a Digital Computer [in Russian], Naukova Dumka, Kiev (1969).
3. F. Siarle, Method of Finite Elements for Elliptical Problems [Russian translation], Mir Moscow (1980).
4. I. I. Lyashko, G. E. Mistetskii, and N. I. Chernyi, ?Numerical approach to calculation of seepage through earth structures of a pumped-storage station,? Gidrotekh. Stroit., No. 2, 9?10 (1981).
5. P. Ya. Polubarinova-Kochina, Theory of Groundwater Movement [in Russian], Nauka, Moscow (1977).