Dear Prof. XXXXX,       Here within enclosed is our paper for consideration to be published on "( Journal name)". The further information about the paper is in the following:      The Title:     XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX    The Authors:   XXXXXXXXXX   XXXXXXXXXXXX  and  XXXXXXXXXX      The authors claim that none of the material in the paper has been pub lished or is under consideration for publication elsewhere.    I am the corresponding author and my address and other information is as fol lows,                Address:    Department of XXXXXXXXX,                            Tsinghua University,                            Beijing,10084,                                           E-mail:     XXXXX@                 Tel:      86-10-62785001                Fax:      86-10-62785001  Thank you very much for consideration!                                                     Sincerely Yours,                                                     Dr. XXXXXXXXXXX