We have now received the referee report(s) on this paper, which is being
considered by XXX. The referee(s) have recommended that substantial changes be made to your paper.
Please can you revise your paper following the referee recommendations, and
then send us the revised version together with a list of the changes you
have made. This will help the referee(s) to make the final decision. Please
note that if you do not fully revise your paper and the referee(s) are not
satisfied with the responses that you have made, your paper may still be
rejected.