by (India)L.E.El'sgol'ts;by (India)L.E.El'sgol'ts; by (India)L.E.El'sgol'ts;by (United Kingdom)B.D.Hassard; by (India)K.P.Bahadur;by (India)S.N.Misra; by (USSR)R.V.Ambartzumian;by (India)L.E.El'sgol'ts; by (India)N.Nopany;by (India)V.Palmer;