Hello guys , I am trying to excute the following :

cbsfpfg `echo "esel"$REE esel`
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where cbsfpfg is an excutable , I am trying somthing like this :

system (qq(cbsfpfg `echo "esel"$REE esel`));

also 

system (cbsfpfg `echo "esel"$REE esel`);
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but I am getting this error :

'cbsfpfg' is not recognized as an internal or external command,
operable program or batch file.
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eventhough it works from the command line but inside the script it doesn't . thanks for any help