found:Work cat.: 96-105431: Geothermal energy training program, 1995:p. i (work cat. is for watersource heatpump technicians; geothermal heating/cooling system)
found:ASTI on FirstSearch, 04/23/96:in abstracts (Geothermal heating and cooling system; Geothermal water heat pump system; ground source heat pumps)