diff -r b1b3f25750f4 -r ae236e935a34 lib/texinputs/isabellesym.sty
--- a/lib/texinputs/isabellesym.sty	Mon Oct 30 18:22:20 2000 +0100
+++ b/lib/texinputs/isabellesym.sty	Mon Oct 30 18:22:49 2000 +0100
@@ -127,7 +127,7 @@
 \newcommand{\isasymLongleftrightarrow}{\isamath{\Longleftrightarrow}}
 \newcommand{\isasymbar}{\isamath{\mid}}
 \newcommand{\isasymhyphen}{\isatext{\rm-}}
-\newcommand{\isasymmacron}{\isatext{\rm\=\relax}}
+\newcommand{\isasyminverse}{\isamath{{}^{-1}}}
 \newcommand{\isasymexclamdown}{\isatext{\rm\textexclamdown}}
 \newcommand{\isasymquestiondown}{\isatext{\rm\textquestiondown}}
 \newcommand{\isasymguillemotleft}{\isatext{\flqq}}  %requires babel