1. Chinese Medicine Institute. 1975.Handbook of Chinese Medicine Preparation, 332Beijing: People's publishing house of health.
2. Wold, s., Martens, H., Wold, H., Ruhe, A. and Kagstrom, B., eds. Proceedings on the Symposium Matrix Pencils, Pitea, 1982. Berlin and Hoidelberg: Springer Verlag. Lecture Notes in Mathematics