@ARTICLE{
author={Ivezic Dejan D,Zivkovic Marija A,Tanaskovic Toma I,Dajic Nenad},
year={2009},
title={An economic model for the appraisal and selection of energy supply system},
journal={APPLIED THERMAL ENGINEERING},
volume={29},
number={8-9},
pages={1440-1446},
document_type={Article},
} 

@ARTICLE{
author={Brkic Dejan,Tanaskovic Toma I},
year={2008},
title={Systematic approach to natural gas usage for domestic heating in urban areas},
journal={ENERGY},
volume={33},
number={12},
pages={1738-1753},
document_type={Article},
}