1. Doesburg, J. J. (1965). Pectic Substances in Fresh and Preserved Fruits and Vegetables. IBVT-Commimieation No. 25. Sprenger Institute, Wageningen, The Netherlands.
2. Pilnik, W. and Voragen, A. G. J. (1970). In: The Biochemistry of Fruits and Their Products. Ed. A. C. Hulme. Academic Press, London, 1, 53–87.
3. Kawabata, A. (1977). Mem. Tokyo Univ. Agric, XIX, 115–200.
4. Rombouts, F. M. and Pilnik, W. (1972), CRC Crit. Rev. Food Technol., 3, 1–26.
5. Macmillan, J. D. and Sheiman, M. I. (1974). In: Food Related Enzymes. Ed. J. R. Whitaker. American Chemical Society, Washington, DC, 101–30.