general markup improvements
diff --git a/Doc/lib/libcmd.tex b/Doc/lib/libcmd.tex
index 4b7a23d..7260b85 100644
--- a/Doc/lib/libcmd.tex
+++ b/Doc/lib/libcmd.tex
@@ -11,7 +11,8 @@
 test harnesses, administrative tools, and prototypes that will
 later be wrapped in a more sophisticated interface.
 
-\begin{classdesc}{Cmd}{\optional{completekey},\optional{stdin},\optional{stdout}}
+\begin{classdesc}{Cmd}{\optional{completekey\optional{,
+                       stdin\optional{, stdout}}}}
 A \class{Cmd} instance or subclass instance is a line-oriented
 interpreter framework.  There is no good reason to instantiate
 \class{Cmd} itself; rather, it's useful as a superclass of an
@@ -20,7 +21,7 @@
 
 The optional argument \var{completekey} is the \refmodule{readline} name
 of a completion key; it defaults to \kbd{Tab}. If \var{completekey} is
-not \code{None} and \module{readline} is available, command completion
+not \constant{None} and \refmodule{readline} is available, command completion
 is done automatically.
 
 The optional arguments \var{stdin} and \var{stdout} specify the 
@@ -44,7 +45,7 @@
 The optional argument is a banner or intro string to be issued before the
 first prompt (this overrides the \member{intro} class member).
 
-If the \module{readline} module is loaded, input will automatically
+If the \refmodule{readline} module is loaded, input will automatically
 inherit \program{bash}-like history-list editing (e.g. \kbd{Control-P}
 scrolls back to the last command, \kbd{Control-N} forward to the next
 one, \kbd{Control-F} moves the cursor to the right non-destructively,
@@ -184,7 +185,7 @@
 \function{raw_input()} to display a prompt and read the next command;
 if false, \method{sys.stdout.write()} and
 \method{sys.stdin.readline()} are used. (This means that by
-importing \module{readline}, on systems that support it, the
-interpreter will automatically support Emacs-like line editing 
+importing \refmodule{readline}, on systems that support it, the
+interpreter will automatically support \program{Emacs}-like line editing 
 and command-history keystrokes.)
 \end{memberdesc}