> 78-XX Optics, electromagnetic theory

78-00 General reference works (handbooks, dictionaries, bibliographies, etc.)	78-01 Instructional exposition (textbooks, tutorial papers, etc.)	78-02 Research exposition (monographs, survey articles)
78-03 Historical (must also be assigned at least one classification number from Section 01)	78-04 Explicit machine computation and programs (not the theory of computation or programming)	78-05 Experimental work
78-06 Proceedings, conferences, collections, etc.	78-99 Optics, electromagnetic theory (not classified at a more specific level)	78AXX General
78MXX Basic methods

78-XX Optics, electromagnetic theory