THROUGHOUT the books treating of hyperbolic functions, although elaborate series for their determination are given, the possibility of calculating them directly from their definitions, by means of ...

VILHELM JØRGENSEN, ON AN INEQUALITY FOR THE HYPERBOLIC MEASURE AND ITS APPLICATIONS IN THE THEORY OF FUNCTIONS, Mathematica Scandinavica, Vol. 4, No. 1 (1956), pp. 113-124 ...

M. Papadimitrakis, On Convexity of Level Curves of Harmonic Functions in the Hyperbolic Plane, Proceedings of the American Mathematical Society, Vol. 114, No. 3 (Mar., 1992), pp. 695-698 ...