An invoice shall be submitted to the purchaser showing the quantity of liquefied petroleum gas sold, expressed in pounds, or gallons, or cubic feet, or other units approved by the secretary of agriculture. When vapor meters reading in approved units other than cubic feet are used, the invoice shall clearly indicate to the purchaser a factor to convert to cubic feet or gallons.
When liquefied petroleum gas is sold at retail by liquid volume from a delivery vehicle, a ticket issued by a liquid meter shall be used to show the quantity delivered in gallons; and the printed ticket shall clearly indicate to the purchaser the gallons of liquefied petroleum gas sold and delivered.
K.S.A. 83-146