Ramanujan unitary one-matching bi-Cayley graphs over finite commutative rings.

Let $ \mathcal {G}_R $ G R denote a unitary one-matching bi-Cayley graph over a finite commutative ring R. In this paper, we give a necessary and sufficient condition for $ \mathcal {G}_R $ G R (respectively, the complement of $ \mathcal {G}_R $ G R and the line graph of $ \mathcal {G}_R $ G R ) to be Ramanujan. [ABSTRACT FROM AUTHOR]