Iracheta v. Holder, 730 F.3d 419 (5th Cir. Sept. 11, 2013) (U.S. citizen born in Mexico of a U.S. citizen father acquired citizenship because under the law of the Mexican state of Tamaulipas where the person was born, his father legitimated him well before he turned twenty-one years old, and so meets the requirements for having acquired U.S. citizenship from his father at birth; court criticized agency for relying on nonexistent provision of Mexican Constitution in denying the claim).