  In the analysis of the Wheeler-DeWitt equation, we have simplified the
Hamiltonian constraint of the Wheeler-DeWitt equation using the coordinate
transformation. The coordinate is choose such that metric becomes diagonal and
as Gaussian normal coordinate. Or we treat small universe so that the metric
become diagonal and universe is covered by Gaussian normal coordinates. We have
solved the Wheeler-DeWitt equation of such universes. Such that universe
contains Biancki I type universe or the black hole universe.
