1. Gronowitz S., Arkiv Kemi, 1953, Vol. 6, P. 283.
2. Gronowitz S., Larsson S., Arkiv Kemi, 1955, Vol. 8, P. 567.
3. Gronowitz S., Arkiv Kemi, 1958, Vol. 13, P. 87.
4. Gronowitz S., Arkiv Kemi, 1958, Vol. 13, P. 231.
5. Campaigne E., LeSuer W. E. M., J. Amer. Chem. Soc., 1948, Vol. 70, P. 1555.