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CUSIP No. 084102102 13-G Page 7 of 9 Pages
EXHIBIT 1 TO SCHEDULE 13G
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NOVEMBER 10, 2000
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MORGAN STANLEY DEAN WITTER & CO. and MILLER ANDERSON & SHERRERD,
LLP hereby agree that, unless differentiated, this Schedule 13G
is filed on behalf of each of the parties.
MORGAN STANLEY DEAN WITTER & CO.
BY: /s/ Dennine Bullard
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Dennine Bullard / Morgan Stanley & Co. Incorporated
MILLER ANDERSON & SHERRERD, LLP
BY: /s/ Paul A. Frick
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Paul A. Frick / Vice President Miller Anderson & Sherrerd, LLP
* Attention. Intentional misstatements or omissions of fact constitute federal
criminal violations (see 18 U.S.C. 1001).
