  The purpose of this note is to spell out the details of the construction of
parametrices for fully elliptic uniformly degenerate pseudodifferential
operators on manifolds $X$ with boundary. Following the original work by
Mazzeo-Melrose on the 0-calculus, the parametrices are shown to have
(polyhomogeneous) conormal Schwartz kernels on the 0-double space, a resolution
of $X^2$. The extended 0-double space introduced by Lauter plays a useful role
in the construction.
