diff --git a/.vimrc b/.vimrc
index 14cf5e0..4f83049 100644
--- a/.vimrc
+++ b/.vimrc
@@ -7,4 +7,4 @@ command Tmomc :r ~/Documents/templates/chapter.mom
 command Tmomg :r ~/Documents/templates/general.mom
 
 " run groff+refer on file
-:command Groff !refer -PS -e -p ~/Documents/bib % | groff -mom -Tpdf >> ${"%"::-4}.pdf 
+:command Groff !p="%"; refer -PS -e -p ~/Documents/bib ${p::-4}.mom | groff -mom -Tpdf >> ${p::-4}.pdf