  The entangling power of a bipartite unitary operation shows the maximum
created entanglement with the product input states. For an arbitrary two-qubit
unitary operation, it is sufficient to consider its normalized operation $U$
with parameters $c_0,c_1,c_2$ and $c_3$. We show how to compute the entangling
power of $U$ when $c_2=c_3$. In particular we construct the analytical
expressions of entangling power of such $U$ for two examples. We also construct
the entangling power of bipartite unitary operations of Schmidt rank two for
any dimensions.
