1. Ahlfors, L.V. Möbius transformations in several dimensions. Ordway Lectures in Mathematics, University of Minnesota (1981).
2. Axler, S., Bourdon, P. and Ramey, W. Harmonic Function Theory. Springer, New York (1992).
3. Burckel, R.B. An Introduction to Classical Complex Analysis. Volume 1, Birkhäuser, Basel (1979).
4. Burgeth, B. A Schwarz Lemma for harmonic and hyperbolic— harmonic functions in higher dimensions. Manuscripta Math. 77, 283– 291 (1992).
5. Hmissi, F. Fonctions harmoniques pour les potentiels de Riesz sur la boule unité. Preprint.