@article{MABA_2009_23_1-2_a5,
     author = {N. Sonmez},
     title = {The {Internal} {Bisector's} {Slope} and {External} {Bisector's} {Slope} on {Poincare} {Upper} {Half} {Plane}},
     journal = {Mathematica balkanica},
     pages = {73},
     publisher = {mathdoc},
     volume = {23},
     number = {1-2},
     year = {2009},
     url = {http://geodesic.mathdoc.fr/item/MABA_2009_23_1-2_a5/}
}