[1] J. Král:
Non-tangential limits of the double distribution. Czech. Mat. J. I4 (89) 1964, 455-482.
MR 0180691
[2] J. Král:
On the logaritmic potential of the double distribution. Czech. Mat. J. 14 (89) 1964, 306-321.
MR 0180690
[3] J. Král:
Some inequalities concerning the cyclic and radial variations of a plane path-curve. Czech. Mat. J. I4 (89) 1964, 271-280.
MR 0180689