@article{BASS_2009_34_1_a0,
     author = {G. H. Fath-Tabar and A. R. Ashrafi and I. Gutman},
     title = {Note on {Estrada}  and $L${-Estrada} indices of graphs},
     journal = {Bulletin de l'Acad\'emie serbe des sciences. Classe des sciences math\'ematiques et naturelles},
     pages = {1 - 16},
     publisher = {mathdoc},
     volume = {34},
     number = {1},
     year = {2009},
     url = {http://geodesic.mathdoc.fr/item/BASS_2009_34_1_a0/}
}