1. Bekefi, G.: 1966, Radiation Processes in Plasma, John Wiley and Sons, New York.
2. Chiu, H. Y. and Occhionero, F.: 1969, Nature
223, 1113.
3. Clark, R. R. and Smith, F. G.: 1969, Nature
221, 724.
4. Craft, H. D., Jr.: 1970, `Radio Observation of the Pulse Profiles and Dispersion Measures of 12 Pulsars’ Ph.D. Thesis, Cornell University (Fig. No. 5. 28 ).
5. Drake, F. D. and Craft, H. D.: 1968, Nature
220, 231.