  The NMR and NQR spectra of $^{63}$Cu in the CuO$_2$ plane of
YBa$_2$Cu$_3$O$_7$ in the superconducting state are discussed in terms of the
phenomenological theory of Ginzburg-Landau type extended to lower temperatures.
We show that the observed spectra, Kumagai {\em et al.}, PRB {\bf 63}, 144502
(2001), can be explained by a standard theory of the Bernoulli potential with
the charge transfer between CuO$_2$ planes and CuO chains assumed.
