35-00 General reference works (handbooks, dictionaries, bibliographies, etc.)
35-01 Instructional exposition (textbooks, tutorial papers, etc.)
35-02 Research exposition (monographs, survey articles)
35-03 Historical (must also be assigned at least one classification number from Section 01)
35-04 Explicit machine computation and programs (not the theory of computation or programming)
35-06 Proceedings, conferences, collections, etc.
35Axx General theory
35Bxx Qualitative properties of solutions
35Cxx Representations of solutions
35Dxx Generalized solutions of partial differential equations
35Exx Equations and systems with constant coefficients [See also 35N05]
35Fxx General first-order equations and systems
35Gxx General higher-order equations and systems
35Hxx Close-to-elliptic equations
35Jxx Partial differential equations of elliptic type [See also 58Jxx, 58J10, 58J20]
35Kxx Parabolic equations and systems [See also 35Bxx, 35Dxx, 35R30, 35R35, 58J35]
35Lxx Partial differential equations of hyperbolic type [See also 58J45]
35Mxx Partial differential equations of special type (mixed, composite, etc.) {For degenerate types, see 35J70, 35K65, 35L80}
35Nxx Overdetermined systems [See also 58Hxx, 58Jxx, 58J10, 58J15]
35Pxx Spectral theory and eigenvalue problems for partial differential operators [See also 47Axx, 47Bxx, 47F05]
35Qxx Equations of mathematical physics and other areas of application [See also 35J05, 35J10, 35K05, 35L05]
35Rxx Miscellaneous topics involving partial differential equations {For equations on manifolds, see 58Jxx; for manifolds of solutions, see 58Bxx; for stochastic PDEs, see also 60H15}
35Sxx Pseudodifferential operators and other generalizations of partial differential operators [See also 47G30, 58J40]