-@item You need an @ref{nncp-exec} program that extracts the sender
-address from mail that arrives via NNCP, and that feeds the mail into
-the Postfix @command{sendmail} command.
+@item You need an @command{@ref{nncp-exec}} program that extracts the
+sender address from mail that arrives via NNCP, and that feeds the mail
+into the Postfix @command{sendmail} command.