1. T.B.Filicheva, E.M.Mogilevskii, and S.P.Papkov, Fibre Chemistry, No.1 (1974).
2. C.W. Tait et al., J.Polymer Sci., 7, 261 (1951).
3. J. Dolby and O. Samuelson, Svensk Papperstidn., 68, 136 (1965).
4. A.A. Konkin and A.B. Pakshver editors, Man-Made Fibre Production Control (in Russian), Khimiya, Moscow (1967).
5. I. Schurz, Koll.-Z., 155, 45 (1957).