ARTHUR ANDERSEN


                   CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS



As independant public accountants, we hereby consent to the incorporation of our
report  included  in  this  Form  8-Ka,  into  the  Company's  previously  filed
Registration  Statements  on Forms S-3 and Forms  S-8 (File  Numbers  333-09917,
333-10117, 333-09911 and 333-09909).


                                                             ARTHUR ANDERSEN LLP


Phoenix, Arizona,
  September 4, 1997.

                                   F-24