1. GAUSS, C.F.Disquisitiones Arithmeticae. G. Fleischer, Leipzig, 1801.
2. GAUSS, C.F. English translation by A.A. Clarke. Yale Univ. Press, New Haven, 1966.
3. GAUSS, C.F. Revised English translation by W.C. Waterhouse. Springer-Verlag, New York, 1986.
4. EISENSTEIN, F.G. Aufgaben. Journal f.d. reine u. angew. Math., 27, 1844, p. 87.
5. EISENSTEIN, F.G. Reprinted in Mathematische Werke, Vol. I, p. 112. Chelsea, Bronx, N.Y., 1975.