diff --git a/Doc/libcgi.tex b/Doc/libcgi.tex
index 56643d0..4d0c5d6 100644
--- a/Doc/libcgi.tex
+++ b/Doc/libcgi.tex
@@ -219,10 +219,12 @@
 HTML.
 \end{funcdesc}
 
-\begin{funcdesc}{escape}{}: convert the characters ``\code{\&}'', ``\code{<}'' and ``\code{>}'' to HTML-safe
+\begin{funcdesc}{escape}{s\optional{\, quote}}: convert the characters
+``\code{\&}'', ``\code{<}'' and ``\code{>}'' in string \var{s} to HTML-safe
 sequences.  Use this if you need to display text that might contain
-such characters in HTML.  To translate URLs for inclusion in the HREF
-attribute of an \code{<A>} tag, use \code{urllib.quote()}.
+such characters in HTML.  If the optional flag \var{quote} is true,
+the double quote character (\code{"}) is also translated; this helps
+for inclusion in an HTML attribute value, e.g. in ``\code{<A HREF="...">}''.
 \end{funcdesc}