@article{DMGT_2000_20_1_a9,
     author = {Chartrand, Gary and Harary, Frank and Zhang, Ping},
     title = {Geodetic sets in graphs},
     journal = {Discussiones Mathematicae. Graph Theory},
     pages = {129--138},
     publisher = {mathdoc},
     volume = {20},
     number = {1},
     year = {2000},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGT_2000_20_1_a9/}
}