A tower of Artin-Schreier extensions of function fields attaining the Drinfeld-Vladut bound. Henning Stichtenoth, Arnaldo Garcia (1995) Inventiones mathematicae
Automorphism groups of Ree type Deligne-Lusztig curves and function fields. Johan P. Hansen, Jens Peter Pedersen (1993) Journal für die reine und angewandte Mathematik