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A characterization of the second-order strong divisibility sequences. The Fibonacci Quarterly, 23 no 2 (1985), pp. 126-132.
MR 0797130
[2] T. N. Shorey A. J. van der Poorten R. Tijdeman, A. Schinzel:
Applications of the Gelfond-Baker method to Diophantine equations. Transcendence theory: advances and applications, pp. 59-77, London 1977.
MR 0472689
[3] L. Skula: Problem 5. Summeг School on Number Theory held at Chlebske September 1983, p. 98, Brno 1985.
[4] V. G. Sprindzuk: Klassiceskiye diofantovy uravneniya ot dvuh neizvestnyh. Moskva 1982.