@article{JGG_2008_12_1_JGG_2008_12_1_a1,
     author = {J. M. Habeb and M. Hajja },
     title = {A {Method} for {Establishing} {Trigonometric} {Inequalities} {Involving} the {Cotangents} of the {Angles} of a {Triangle}},
     journal = {Journal for geometry and graphics},
     pages = {11--21},
     publisher = {mathdoc},
     volume = {12},
     number = {1},
     year = {2008},
     url = {http://geodesic.mathdoc.fr/item/JGG_2008_12_1_JGG_2008_12_1_a1/}
}