Reference

A:.J. Nunn, I. M. Reiter, K.- H. Häberle, H. Werner, C. Langebartels, H. Sandermann, C. Heerdt, P. Fabian, Rainer Matyssek (2002): "Free Air" Ozone Canopy Fumigation in an Old- Growth Mixed Forest: Concept and Observations in Beech. – Phyton, Annales Rei Botanicae, Horn – 42_3: 105 - 119.