5Benavides L G, Escudero A, Perez-Garca F. Seed germination of high mountain Mediterranean species:altitudinal, interpopulation and interannual variability[J].Ecolgy Research,2005(20):433-444.
6Bewley J D, Black M. Seeds: Physiology of development and germination[M]. New York: Plenum Press, 1994:25-45.
7Viswanath S, Singh R P, Thapliyal R C. Seed germination patterns in a Himalayan moist temperate forest[J]. Tropical Ecology, 2002,43(2):265-273.