by (USSR)I.Duncan; (United States)C.Payne; by (USSR)M.L.Krasonv;by (United States)S.Lang; by (USSR)A.Ramakrishnan;by (United States)C.Harper; by (USSR)A.O.Gelfond;by (United States)A.H.Nayfeh; by (USSR)M.Prives;by (United States)N.S.Sahana; by (USSR)I.A.Rrezanov;by (United States)N.C.Barford; by (USSR)I.FROLOV;by (United States)P.EDWARDS; by (USSR)A.V.Efimov;by (United States)M.Mandl; by (USSR)M.Baryshnikov;by (United States)C.R.Jones; by (USSR)O.V.Chernyak;by (United States)V.M.Faires;