@article{10_4064_ap83_2_9,
     author = {Armen Edigarian},
     title = {A note on {Costara's} paper},
     journal = {Annales Polonici Mathematici},
     pages = {189--191},
     publisher = {mathdoc},
     volume = {83},
     number = {2},
     year = {2004},
     doi = {10.4064/ap83-2-9},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap83-2-9/}
}