1. Aikens R.S., Harvey J.W., Lynds C.R.: 1976, IAU Colloq. No. 40, 25, Eds. M. Duchesne, G. Lelievre, Paris-Meudon Obs.
2. Beauchamp K.G.: 1975, Walsh functions and their applications, Academic Press, London.
3. Boksenberg A.: 1976, IAU Colloq. No. 40, 13.
4. Cenalmore V.: 1976, IAU Colloq. No. 40, 16.
5. Choisser J.P.: 1976, IAU Colloq. No. 40, 27.