Davis, Bob; Palmiter, Larry S. & Siegel, Jeff. Field Measurements of Heating Efficiency of Electric Forced-Air Furnaces in Six Manufactured Homes., report, July 26, 1994; (https://digital.library.unt.edu/ark:/67531/metadc1278222/m1/1/: accessed April 23, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .