NX1-260 General NX280-410 Study and teaching. Research NX411-415 Competitions NX420-430 Exhibitions NX440-632 History of the arts NX650-694 Special subjects, characters, persons,
religious arts, etc. NX700-750 Patronage of the arts NX760-770 Administration of the arts NX775-777 Voluntarism in the arts NX798-820 Arts centers and facilities Subclass NX