For purposes of RCW 82.14A.010, the state department of revenue is hereby authorized and directed to promulgate, pursuant to the provisions of chapter 34.05 RCW, rules establishing uniform methods of division of gross income of the business of a single taxpayer between those cities, towns and unincorporated areas in which such taxpayer has a place of business.
[ 1972 ex.s. c 134 § 3.]