by (USSR)K.Spidchenke;by (United Kingdom)T.R.Williams; by (USSR)V.A.Ugarov;by (United Kingdom)C.M.Will; by (USSR)A.Yariv;by (United Kingdom)J.M.Ziman; by (USSR)I.E.Irodov;by (United Kingdom)K.F.Riley; by (USSR)I.S.Dmitriev;by (United Kingdom)P.W.Atkins; by (USSR)M.Vygodsky;by (United Kingdom)J.L.Bell; by (USSR)I.V.Savelyev;by (United Kingdom)T.K.Aun; by (USSR)M.L.Krasnov;by (United Kingdom)L.M.Delves; by (United States)J.Lowe;by (United Kingdom)P.Williams; by (USSR)A.Starkov;by (United Kingdom)A.Sharp;