4200  General reference works (handbooks, dictionaries, bibliographies, etc.)


4201  Instructional exposition (textbooks, tutorial papers, etc.)


4202  Research exposition (monographs, survey articles)


4203  Historical (must also be assigned at least one classification number from Section 01)


4204  Explicit machine computation and programs (not the theory of computation or programming)


4206  Proceedings, conferences, collections, etc.



42Axx  Fourier analysis in one variable

42Bxx  Fourier analysis in several variables {For automorphic theory, see mainly 11F30}

42Cxx  Nontrigonometric Fourier analysis
