Tex. Natural Resources Code § 112.011: BILL OF SALE.

Before purchasing or acquiring by exchange used materials, a dealer, broker, or peddler shall require that a bill of sale for the used materials be executed by the seller or the person who exchanges the materials. The dealer, broker, or peddler shall keep a copy of each bill of sale at his place of business.

Acts 1977, 65th Leg., p. 2592, ch. 871, art. I, Sec. 1, eff. Sept. 1, 1977. Amended by Acts 1981, 67th Leg., p. 2339, ch. 573, Sec. 2, eff. Aug. 31, 1981.