1. J. C. Saunders and K. K. Frish, Chemistry of Polyurethanes [Russian translation], Khimiya, Moscow (1968).
2. H. J. Fabris, Adv. Urethane Sci. Technol.,6, 173 (1978).
3. T. Timm, Kautsch. Gummi Kunst.,36, 257 (1983).
4. E. Dyer and G. G. Wright, J. Am. Chem. Soc.,81, 2138 (1959).
5. K. B. Wiberg, Tetrahedron,24, 1083 (1968).