Some isomorphic classes for noncanonical hypercomplex number systems of   dimension 2
  Building of some isomorphic classes for noncanonical hypercomplex number systems o dimension 2 is described. In general case, such systems with specific constraints to structural constants can be isomorphic to complex, dual or double number system. Isomorphic transition between noncanonical hypercomplex number systems of the general form and diagonal form is built. 
Yakiv O. Kalinovsky, Dmitry V. Lande, Yuliya E. Boyarinova, Iana V.   Khitsko
cs.NA