diff --git a/Doc/lib/libmailbox.tex b/Doc/lib/libmailbox.tex
index 8db4c91..42bdfda 100644
--- a/Doc/lib/libmailbox.tex
+++ b/Doc/lib/libmailbox.tex
@@ -1,4 +1,5 @@
 \section{Standard Module \sectcode{mailbox}}
+\label{module-mailbox}
 \stmodindex{mailbox}
 
 \renewcommand{\indexsubitem}{(in module mailbox)}
@@ -7,7 +8,7 @@
 access to mail messages in a (unix) mailbox.
 
 \begin{funcdesc}{UnixMailbox}{fp}
-Access a classic unix-style mailbox, where all messages are contained
+Access a classic \UNIX{}-style mailbox, where all messages are contained
 in a single file and separated by ``From name time'' lines. \var{Fp}
 is the file object pointing to the mailbox file.
 \end{funcdesc}
diff --git a/Doc/libmailbox.tex b/Doc/libmailbox.tex
index 8db4c91..42bdfda 100644
--- a/Doc/libmailbox.tex
+++ b/Doc/libmailbox.tex
@@ -1,4 +1,5 @@
 \section{Standard Module \sectcode{mailbox}}
+\label{module-mailbox}
 \stmodindex{mailbox}
 
 \renewcommand{\indexsubitem}{(in module mailbox)}
@@ -7,7 +8,7 @@
 access to mail messages in a (unix) mailbox.
 
 \begin{funcdesc}{UnixMailbox}{fp}
-Access a classic unix-style mailbox, where all messages are contained
+Access a classic \UNIX{}-style mailbox, where all messages are contained
 in a single file and separated by ``From name time'' lines. \var{Fp}
 is the file object pointing to the mailbox file.
 \end{funcdesc}