1. P. F. Kalnyn, S. A. Hiller, and M. V. Tarvid (Shimanskaya), Izv. AN LatvSSR, 3, 443, 1951.
2. S. A. Hiller and M. V. Tarvid (Shimanskaya), Izv. AN LatvSSR, 11, 89, 1952.
3. S. A. Hiller, M. V. Shimanskaya, and I. I. Ioffe, collection: Questions on the Use of Pentose-Containing Raw Material [in Russian], Izd-vo AN LatvSSR, Riga, p. 263, 1958.
4. N. A. Milas and W. L. Walsch, J. Am. Chem. Soc., 57, 1389, 1935.
5. US patent no. 2118567, 1938.