Columbia subject headings:
Associative algebras.
Associative rings.
Categories (Mathematics)
Sheaf theory.
Toposes.
Harvard subject headings:
Associative algebras.
Associative rings.
Categories (Mathematics)
Sheaf theory.
Toposes.
Princeton subject headings:
Associative algebras.
Associative rings.
Categories (Mathematics)
Sheaf theory.
Toposes.