Insa and Pauer presented a basic theory of Groebner basis for differential
operators with coefficients in a commutative ring in 1998, and a criterion was
proposed to determine if a set of differential operators is a Groebner basis.
In this paper, we will give a new criterion such that Insa and Pauer's
criterion could be concluded as a special case and one could compute the
Groebner basis more efficiently by this new criterion