Source: L. 64: p. 606, § 20. C.R.S. 1963: § 123-31-20. L. 70: p. 179, § 27. L. 71: pp. 563, 1149, §§ 48, 5. L. 72: pp. 316, 567, §§ 45, 45. L. 74: (1) amended, p. 375, § 5, effective March 21; (5)(a) amended, p. 419, § 68, effective April 11. L. 80: (4) amended, p. 409, § 7, effective January 1, 1981. L. 87: (2) amended, p. 314, § 46, effective July 1. L. 92: Entire article amended, p. 827, § 31, effective January 1, 1993.