1. Letac, G. (1978). Advanced problem 6230.Am. Math. Monthly 85, 686. Solution by L. Takács87, 142 (1980).
2. El Bachir, M. (1983).L'enveloppe convexe du mouvement brownien. Thèse de 3ème cycle, Toulouse.
3. Santaló, L. Integral Geometry, inStudies in Global Geometry and Analysis, S. S. Chern (ed.), MAA Studies in Mathematics4, 147?193.
4. Feller, W. (1966).An Introduction to Probability Theory and Its Applications, Vol. 2, Wiley, New York.