CUSIP No.      231021106             13G                       Page 7 of 9 Pages



                          EXHIBIT 1 TO SCHEDULE 13G
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                               August 15, 1997
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         MORGAN STANLEY, DEAN WITTER, DISCOVER & CO. and MILLER ANDERSON & 

         SHERRERD LLP, hereby agree that, unless differentiated, this Schedule 

         13G is filed on behalf of each of the parties.
         

            MILLER ANDERSON & SHERRERD LLP

   BY:      /s/ Donald P. Ryan 
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            Donald P. Ryan / Vice President Morgan Stanley Asset Management Inc.

            MORGAN STANLEY, DEAN WITTER, DISCOVER & CO.

   BY:      /s/ Bruce Bromberg 
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            Bruce Bromberg / Morgan Stanley & Co. Incorporated