EXHIBIT 1
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AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G
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Each of the undersigned hereby affirms that it is individually eligible to use
Schedule 13G, and agrees that this Schedule 13G is filed on its behalf.
Dated: May 12, 2008
IMPULSORA de FONDOS BANAMEX, S.A. de C.V.
By: /s/ ▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇▇▇
Title: Finance Director
ACCIONES y VALORES BANAMEX, S.A. de C.V.
By: /s/ ▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇▇▇
Title: Finance Director
GRUPO FINANCIERO BANAMEX, S.A. de C.V.
By: /s/ ▇▇▇▇▇▇ De ▇▇▇▇▇ ▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇▇ De ▇▇▇▇▇ ▇▇▇▇▇▇▇
Title: Senior Legal Counsel
CITICORP (MEXICO) HOLDINGS LLC
By: /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇
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Name: ▇▇▇▇▇▇▇ ▇. ▇▇▇▇
Title: President
CITIGROUP INC.
By: /s/ Riqueza ▇. ▇▇▇▇▇▇▇
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Name: Riqueza ▇. ▇▇▇▇▇▇▇
Title: Assistant Secretary
