1. Rerat, B., Dauphin, G., Kergomard, A., Rerat, Cl.: Compt. Rend. C 262 (1966) 1318; C.A. 65 (1966) 6430h.
2. Jones, N. D., Marsh, R. E., Richards, J. H.: Acta Cryst. 19 (1965) 333; C.A. 63 (1965) 9160h.
3. de Vere, R. F.: Acta Cryst. 19 (1965) 681.
4. Deshapande, S. V., Meredith, C. C., Pasternak, R. A.: Acta Cryst. B 24 (1968) 1396; C.A. 69 (1968) 111042j.
5. Kari, R., Kunchur, N. R.: Can. J. Chem. 42 (1964) 2628; C.A. 62 (1965) 89g.