LANSING, Mich. — The state’s retail propane marketers have approved a referendum to establish the funding mechanism for the Michigan Propane Commission, created in statute last year. The initial assessment will be at the rate of 1/10 of 1 cent per gallon upon odorized propane sold and placed into commerce in the state. The results of the referendum were certified today by Michigan Department of Agriculture and Rural Development Director Gary McDowell.