ASHRAE (1995) Commercial / Institution ground source heat pump engineering manual. Atlanta, USA.
 Sanaye S, Niroomand B (2009) Thermal-economic modeling and optimization of vertical ground-coupled heat pump. Energ Convers Manage 50: 1136-1147.
 Lubis L, Kanglu M, Dincer I, Rosen M (2011) Thermodynamic analysis of a hybrid geothermal heat pump system. Geothermics 40: 223-228.
 Amin ZM, Hawlader MNA (2013) A review on solar assisted heat pump in Singapore. Renew Sustainable Energy Rev 26: 286-293.
 Hepbasli A (2005) Thermodynamic analysis of a ground-source heat pump system for district heating. Int J Energ Res 29(7): 671-678.
 Sayyadi H, Amlashi E, Amidpour M (2009) Multi-objective optimization of a vertical ground source heat pump using evolutionary algorithm. Energ Convers Manage 50: 2035-2046.
 Bi Y, Wang X, Liu Y, Zhang H, Chen L (2009) Comprehensive exergy analysis of ground-source heat pump system for both building heating and cooling mode. Appl Energ 86: 2560-2565.
 Ma GY, Chai QH (2004) Characteristics of an improved heat pump cycle for cold region. Appl Energ 77: 235-247.
 Self SJ, Rosen MA, Reddy BV (2012) Energy analysis and comparison of advanced vapor compression heat pump arrangement, in: The Canadian conference on building simulation. Halifax, Nova Scotia, 1-4 may, 463-477.
 Self SJ, Reddy BV, Rosen MA(2013) Ground source heat pumps for heating: parametric energy analysis of a vapor compression cycle utilizing an economizer arrangement. Appl Therm Eng 52: 245-254.
 Wang H, Peterson R, Herron T (2011) Design study of configuration on system COP for a combined ORC an VCC. Energy 36: 4809-4820.