1. Combinatorial Theory;Aigner,1979
2. Catalan-like numbers and determinants;Aigner;J. Combin. Theory Ser. A,1999
3. Catalan and other numbers: a recurrent theme;Aigner,2001
4. C. Banderier, S. Schwer, Why Delannoy's numbers?, May 2002, Lattice Paths’02.
5. Combinatorial Species and Tree-like Structures;Bergeron,1998