NATIONAL GROUNDWATER ASSOCIATION - www.ngwa.org

CALIFORNIA GROUNDWATER ASSOCIATION - www.cgwa.org

INTERNATIONAL GROUND SOURCE HEAT PUMP ASSOCIATION - www.igshpa.okstate.edu

GEOTHERMAL HEAT PUMP CONSORTIUM - www.geoexchange.org

LEEDs - www.buildinggreen.com

MY GREEN COMFORT - www.mygreencomfort.com