Reference

V. F. D. Thomas, E. Hiltbrunner, S. Braun, W. Flückiger (2002): Changes in Root Starch Contents of Mature Beech (Fagus sylvatica L.) Along an Ozone and Nitrogen Gradient in Switzerland. – Phyton, Annales Rei Botanicae, Horn – 42_3: 223 - 228.