1. V. I. Antipov and V. V. Lebedev, Heat Transfer, 1970, in: Fourth International Transfer Conf., Paris-Versailles, 1970, American Elsevier, Amsterdam (1970), Vol. 1, Zh. Prikl. Mekh. Tekh. Fiz., No. 3 (1973).
2. A. N. Tikhonov, Dokl. Akad. Nauk SSSR,151, No. 3 (1963).
3. A. N. Tikhonov and V. Ya. Arsenin, Methods of Solving Incorrect Problems [in Russian], Nauka, Moscow (1974).
4. A. G. Kolesnikov and G. A. Martynov, Materials on Laboratory Investigations of Frozen Soils [in Russian], Vol. 1, Izd. Akad. Nauk SSSR, Moscow (1953), p. 13.
5. B. A. Boley, J. Math. Phys.,40, No. 4 (1961).