0500  General reference works (handbooks, dictionaries, bibliographies, etc.)


0501  Instructional exposition (textbooks, tutorial papers, etc.)


0502  Research exposition (monographs, survey articles)


0503  Historical (must also be assigned at least one classification number from Section 01)


0504  Explicit machine computation and programs (not the theory of computation or programming)


0506  Proceedings, conferences, collections, etc.



05Axx  Enumerative combinatorics

05Bxx  Designs and configurations {For applications of design theory, see 94C30}

05Cxx  Graph theory {For applications of graphs, see 68R10, 90C35, 94C15}

05Dxx  Extremal combinatorics

05Exx  Algebraic combinatorics
