unexpected EOF while looking for matching ``'

Guys can you please help on this below is the script and the underlined one is the line number where we are getting the error

#!/bin/sh

DEBUGFS=`which debugfs.ocfs2`

usage() {

echo "usage: stat_sysdir.sh -d sda1,sdb1"

exit 1;

}

OPTIND=1

while getopts "d:" args

do

case "$args" in

d) devices="$(echo $OPTARG | sed 's/,/ /g')";

esac

done;

if [ -z "$devices" ] ;

then

usage ;

fi

for i in $devices

do

DEV=/dev/$i

echo "Device: ${DEV}"

SLOTS=`echo "stats" | ${DEBUGFS} -n ${DEV} | awk '/Max Node Slots:/ { print $4 }'`

if [ -z ${SLOTS} ]

then

continue;

fi

echo " superblock"

echo "stats" | ${DEBUGFS} -n ${DEV}