Tex. Nat. Res. Code § 61.166
Acts 1977, 65th Leg., p. 2486, ch. 871, art. I, Sec. 1, eff. Sept. 1, 1977.
Amended by Acts 1985, 69th Leg., ch. 267, art. 2, Sec. 75, eff. Sept. 1, 1985;
Acts 1993, 73rd Leg., ch. 679, Sec. 63, eff. Sept. 1, 1993;
Acts 1995, 74th Leg., ch. 399, Sec. 2, eff. Aug. 28, 1995.