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2. Midland, South Dakota geothermal district-heating;Lund;Geo-Heat Center Quarterly Bulletin,1997
3. The Oregon Institute of Technology geothermal heating system—then and now;Boyd;Geo-Heat Center Quarterly Bulletin,1999
4. Klamath Falls geothermal district-heating systems;Brown;Geo-Heat Center Quarterly Bulletin,1999
5. Reconstruction of a Pavement Geothermal Deicing System;Lund;Geo-Heat Center Quarterly Bulletin,1999