Editing Quaternion (section)

==== Commutative subrings ====
The relationship of quaternions to each other within the complex subplanes of <math>\mathbb H</math> can also be identified and expressed in terms of commutative [[subring]]s. Specifically, since two quaternions {{mvar|p}} and {{mvar|q}} commute (i.e., {{math|''p q'' {{=}} ''q p''}}) only if they lie in the same complex subplane of <math>\mathbb H</math>, the profile of <math>\mathbb H</math> as a union of complex planes arises when one seeks to find all commutative subrings of the quaternion [[ring (mathematics)|ring]].