\input ../eplain

\fmtversion

$$\commdiag{Y&\mapright^f&E\cr \mapdown&\arrow(3,2)\lft{f_t}&\mapdown\cr
Y\times I&\mapright^{\bar f_t}&X}$$

\end

From DYMACEK@fs.sciences.WLU.EDU Fri Apr 15 09:21:12 1994
To: kb@cs.umb.edu
From: "Wayne M. Dymacek"  <DYMACEK@fs.sciences.WLU.EDU>
Date:     Fri, 15 Apr 1994 9:19:15 EDT