"An Analysis of Rigid Urethane Foam Insulation Effectiveness," G. F. Baumann, SPI Technical Conference, October 1977
2.
"An Assessment of the Thermal Performance of Rigid Polyurethane and Polyisocyanurate Foam Insulations for Use in Building Construction" SPI Bulletin U-108, August 1979.
3.
"Sampling Faced Foam Insulation Board for Heat Flow Meter Thermal Performance Testing" M. Sherman, ASTM Special Technical Publication 718, 1980, pp. 298-306.