Mathematical Sciences Classification System
16Hxx - Algebras and orders 
{For arithmetic aspects, see  11R52,  11R54,  11S45; for representation theory, see  16G30}
                    - 
                            
                            16H05Separable algebras (e.g., quaternion algebras, Azumaya algebras, etc.)
 - 
                            16H10Orders in separable algebras
 - 
                            16H15Commutative orders
 - 
                            16H20Lattices over orders
 - 
                            16H99None of the above, but in this section