We firstly prove that -times integrated -resolvent operator function (( , )-ROF) satisfies a functional equation which extends that of -times integrated semigroup and -resolvent operator function. Secondly, for the inhomogeneous -Cauchy problem ( ) = ( ) + ( ), ∈ (0, ), (0) = 0 , (0) = 1 , if is the generator of an ( , )-ROF, we give the relation between the function V( ) = , ( ) 0 + ( 1 * , )( ) 1 + ( −1 * , * )( ) and mild solution and classical solution of it. Finally, for the problem V( ) = V( ) + +1 ( ) , > 0, V ( ) (0) = 0, = 0, 1, . . ., − 1, where is a linear closed operator. We show that generates an exponentially bounded ( , )-ROF on a Banach space if and only if the problem has a unique exponentially bounded classical solution V and V ∈ 1 loc (R + , ). Our results extend and generalize some related results in the literature.