  A shape of the unitary triangle versus a CP violating parameter \delta
depends on the phase conventions of the CKM matrix, because the CP violating
parameter \delta cannot directly be observed, so that it is not
rephasing-invariant. In order to seek for a clue to the quark mass matrix
structure and the origin of the CP violation, the dependence of the unitary
triangle shape on the parameter \delta is systematically investigated.
