This package defines the subeqnarray and subeqnarray*
environments, which behave like the corresponding eqnarray and
eqnarray* environments, except that the individual lines are
numbered like 1a, 1b, 1c, etc. To refer to these numbers an
extra label command \slabel is provided. Users are urged to
consider the alignment capabilities of the amsmath bundle,
which produce better results than eqnarray-related macros.