@article{JGG_2004_8_1_JGG_2004_8_1_a4,
     author = {E. Kozniewski },
     title = {Geometry of {Roofs} from the {View} {Point} of {Graph} {Theory}},
     journal = {Journal for geometry and graphics},
     pages = {41--58},
     publisher = {mathdoc},
     volume = {8},
     number = {1},
     year = {2004},
     url = {http://geodesic.mathdoc.fr/item/JGG_2004_8_1_JGG_2004_8_1_a4/}
}