EXHIBIT A
The undersigned, Ziff Asset Management, L.P., a Delaware limited
partnership, PBK Holdings, Inc., a Delaware corporation, and Xxxxxx X.
Xxxxxxx, hereby agree and acknowledge that the information required by this
Schedule 13G, to which this Agreement is attached as an exhibit, is filed
on behalf of each of them. The undersigned further agree that any further
amendments or supplements thereto shall also be filed on behalf of each of
them.
Dated: October 3, 2003.
ZIFF ASSET MANAGEMENT, L.P.
By:PBK Holdings, Inc., its general partner
By:/s/ Xxxxxxxxx X. Xxxxx
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Name: Xxxxxxxxx X. Xxxxx
Title: Vice President
PBK HOLDINGS, INC.
By:/s/ Xxxxxxxxx X. Xxxxx
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Name: Xxxxxxxxx X. Xxxxx
Title: Vice President
By:/s/ Xxxxxx X. Xxxxxxx
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Name: Xxxxxx X. Xxxxxxx
