47-00 General reference works (handbooks, dictionaries, bibliographies, etc.)
47-01 Instructional exposition (textbooks, tutorial papers, etc.)
47-02 Research exposition (monographs, survey articles)
47-03 Historical (must also be assigned at least one classification number from Section 01)
47-04 Explicit machine computation and programs (not the theory of computation or programming)
47-06 Proceedings, conferences, collections, etc.
47Axx General theory of linear operators
47Bxx Special classes of linear operators
47Cxx Individual linear operators as elements of algebraic systems
47Dxx Groups and semigroups of linear operators, their generalizations and applications
47E05 Ordinary differential operators [See also 34Bxx, 34Lxx]
47F05 Partial differential operators [See also 35Pxx, 58Jxx]
47Gxx Integral, integro-differential, and pseudodifferential operators [See also 58Jxx]
47Hxx Nonlinear operators and their properties {For global and geometric aspects, see 58-XX, especially 58Cxx}
47Jxx Equations and inequalities involving nonlinear operators [See also 46Txx] {For global and geometric aspects, see 58-XX}
47Lxx Linear spaces and algebras of operators [See also 46Lxx]
47Nxx Miscellaneous applications of operator theory [See also 46Nxx]
47Sxx Other (nonclassical) types of operator theory [See also 46Sxx]