1. T. Sándor, A. Somogyi andF. Telbisz:Suppl. Nuovo Cimento,16, 209 (1960).
2. A. I. Kuzmin:Proc. of Moscow Conf. on Cosmic Rays, Vol.4 (Moscow, 1960), p. 252.
3. T. Sándor, A. Somogyi andF. Telbisz:Abh. des Symposiums für Geomagneismus in Berlin (Berlin, Juni 1960), in the press.
4. H. Cramer:Mathematical Methods of Statistics (Princeton, 1954), p. 536.