@article{01208015,
title = {On the area of a polygon in the hyperbolic plane.},
journal = {Beitr\"age zur Algebra und Geometrie},
volume = {39},
year = {1998},
pages = {423-432},
zbl = {0917.51019},
language = {en},
url = {http://dml.mathdoc.fr/item/01208015}
}
Kántor, Sándor. On the area of a polygon in the hyperbolic plane.. Beiträge zur Algebra und Geometrie, Tome 39 (1998) pp. 423-432. http://gdmltest.u-ga.fr/item/01208015/