@ARTICLE{
author={Gutman Ivan,Furtula Boris,Kovijanic-Vukicevic Zana,Popivoda Goran},
year={2015},
title={On Zagreb Indices and Coindices},
journal={MATCH-COMMUNICATIONS IN MATHEMATICAL AND IN COMPUTER CHEMISTRY},
volume={74},
number={1},
pages={5-16},
document_type={Review},
} 

@ARTICLE{
author={Kovijanic-Vukicevic Zana,Stevanovic Dragan P},
year={2013},
title={Bicyclic graphs with extremal values of PI index},
journal={DISCRETE APPLIED MATHEMATICS},
volume={161},
number={3},
pages={395-403},
document_type={Article},
}