Reduction of heat loss in the district heating network by the replacement of pipe insulation using prefabricated polyurethane foam shellsMašatin, Vladislav; Volkova, Anna; Hlebnikov, AleksandrDHC13 : the 13th International Symposium on District Heating and Cooling : September 3rd to September 4th, 2012, Copenhagen, Denmark2013 / p. 163-166