  In this paper, the third-order Jacobsthal generalized quaternions are
introduced. We use the well-known identities related to the third-order
Jacobsthal and third-order Jacobsthal-Lucas numbers to obtain the relations
regarding these quaternions. Furthermore, the third-order Jacobsthal
generalized quaternions are classified by considering the special cases of
quaternionic units. We derive the relations between third-order Jacobsthal and
third-order Jacobsthal-Lucas generalized quaternions.
