discussed Cited "see" Charles William Cannon v. State of Alabama See Ross v. Texas, 474 F.2d 1150, 1154 (5th Cir. 1973), cert. denied, 414 U.S. 850 , 94 S.Ct. 141 , 38 L.Ed.2d 98 (1973) (conviction would be invalid if prosecutor had withheld “an eyewitness . . . who would have testified that [defendant] was not the robber”); Comment, Brady v. Maryland and the Prosecutor’s Duty to Disclose, 40 U.Chi.L.Rev. 112, 125 (1972), quoted with approval, United States v. Agurs, 427 U.S. 97 , 112 n.21, 96 S.Ct. 2392 , 2402 n.21, 49 L.Ed.2d 342 , 355 n.21 (1976). 11 .