1. Advanced Combinatorics;Comtet,1974
2. Integral Representation and the Computation of Combinatorial Sums;Egorychev;Amer. Math. Soc. Translations,1984
3. Concrete Mathematics;Graham,1988
4. Combinatorial Enumeration;Goulden,1983
5. Combinatorial Identities;Riordan,1968