1. Lattice Theory;Birkhoff,1967
2. Advanced Combinatorics;Comtet,1974
3. Studies in partitions and permutations;Doubilet,1973
4. On the foundations of combinatorial theory. VI. The idea of generating function;Doubilet,1972
5. Mobius Functions, Incidence Algebras and Power Series Representations;Dür,1986