Indexing of COMP

--- a/doc-src/Ref/thm.tex	Thu May 11 10:38:30 1995 +0200
+++ b/doc-src/Ref/thm.tex	Thu May 11 10:42:19 1995 +0200
@@ -595,7 +595,7 @@
 \[ (\List{\phi@1; \ldots; \phi@{i-1}; \phi@{i+1}; \ldots; \phi@n} \Imp \phi)s.
 \]
 
-\item[\tt $thm@1$ COMP $thm@2$] 
+\item[$thm@1$ \ttindexbold{COMP} $thm@2$] 
 calls \hbox{\tt compose ($thm@1$, 1, $thm@2$)} and returns the result, if
 unique; otherwise, it raises exception~\xdx{THM}\@.  It is
 analogous to {\tt RS}\@.