## Mathematical Subject Classification – MSC2010

General reference works (handbooks, dictionaries, bibliographies, etc.) 25

Instructional exposition (textbooks, tutorial papers, etc.) 482

Research exposition (monographs, survey articles) 565

Explicit machine computation and programs (not the theory of computation or programming) 17

Topological spaces and generalizations (closure spaces, etc.) 2712

Several topologies on one set (change of topology, comparison of topologies, lattices of topologies) 1379

Convergence in general topology (sequences, filters, limits, convergence spaces, etc.) 2185

Cardinality properties (cardinal functions and inequalities, discrete subsets) [See also 03Exx] [For ultrafilters, see 54D80] 2415

Special maps on topological spaces (open, closed, perfect, etc.) 3787

Absolute neighborhood extensor, absolute extensor, absolute neighborhood retract (ANR), absolute retract spaces (general properties) [See also 55M15] 1145

Connected and locally connected spaces (general aspects) 1360

Lower separation axioms ($T_0$--$T_3$, etc.) 1908

Higher separation axioms (completely regular, normal, perfectly or collectionwise normal, etc.) 1806

Noncompact covering properties (paracompact, Lindelöf, etc.) 3471

Extensions of spaces (compactifications, supercompactifications, completions, etc.) 2665

Special constructions of spaces (spaces of ultrafilters, etc.) 352

Descriptive set theory (topological aspects of Borel, analytic, projective, etc. sets) [See also 03E15, 26A21, 28A05] 1427