EXHIBIT 99.1
AGREEMENT REGARDING JOINT FILING UNDER
UNDER RULE 13D-1(K) OF THE EXCHANGE ACT
In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as
amended, each of the undersigned agrees to the filing on behalf of each of a
Statement on Schedule 13G, and all amendments thereto, with respect to American
Depositary Shares, representing Series B Preferred Shares of Nortel Inversora
S.A.
Date: February 12, 2007
/s/ Xxxxx X. Xxxxxx
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Xxxxx X. Xxxxxx
Renaissance Technologies Corp.
By: /s/ Xxxx Xxxxxx
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Xxxx Xxxxxx
Vice President
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