diff --git a/xml/best-match.sh b/xml/best-match.sh
index ea3d4ba470..6d9ffb7219 100755
--- a/xml/best-match.sh
+++ b/xml/best-match.sh
@@ -1,46 +1,46 @@
-#!/bin/bash
+#!/bin/sh
 
 base=$1; shift
 target=$1; shift
 destination=$1; shift
 prefix=$1; shift
 
 best="0.0"
 candidates=$(ls -1 ${base}-*.rng 2>/dev/null)
 for rng in $candidates; do
     case $rng in
 	${base}-${target}.rng)
 	    best=${target}
 	    break
 	    ;;
 	*next*)
 	    : skipping $rng
 	    ;;
 	*) 
 	    v=$(echo $rng | sed -e "s/${base}-//" -e 's/.rng//')
 	    : comparing $v with $target
 
 		echo | awk -v n1="$v" -v n2="${best}"  '{if (n1>n2) printf ("true"); else printf ("false");}' |  grep -q "true"
 	    if [ $? -eq 0 ]; then
 		: $v beats the previous ${best} for $target
 		if [ ${target} = next ]; then
 		    best=$v
 		else
 			echo | awk -v n1="$v" -v n2="${target}"  '{if (n1<n2) printf ("true"); else printf ("false");}' |  grep -q "true"
 		    if [ $? -eq 0 ]; then
 			: $v is still less than $target, using
 			best=$v
 		    fi
 		fi
 	    fi
 	    ;;
     esac
 done
 
 if [ "x${best}" != "x0.0" ]; then
     if [ "x$destination" = x ]; then
 	echo ${base}-${best}.rng
     else
 	echo "$prefix<externalRef href=\"${base}-${best}.rng\"/>" >> ${destination}
     fi
 fi