Fixed index references to modules.
diff --git a/Doc/lib/libhtmllib.tex b/Doc/lib/libhtmllib.tex
index edae551..8405ad1 100644
--- a/Doc/lib/libhtmllib.tex
+++ b/Doc/lib/libhtmllib.tex
@@ -19,10 +19,10 @@
 provided in the \code{formatter} module; refer to the documentation
 for that module for information on the formatter interface.
 \index{SGML}
-\stmodindex{sgmllib}
+\refstmodindex{sgmllib}
 \ttindex{SGMLParser}
 \index{formatter}
-\stmodindex{formatter}
+\refstmodindex{formatter}
 
 The following is a summary of the interface defined by
 \code{sgmllib.SGMLParser}: