Humus, its structure and role in agriculture and environment. Proceedings of the 10th symposium humus et planta, held in Prague August 1991. J. Kubát (ed.). - (Developments in agricultural and managed-forest ecology; 25).

Holm Jakobsen, B. (1993). Humus, its structure and role in agriculture and environment. Proceedings of the 10th symposium humus et planta, held in Prague August 1991. J. Kubát (ed.). - (Developments in agricultural and managed-forest ecology; 25). Geografisk Tidsskrift, 93. Hentet fra https://tidsskrift.dk/geografisktidsskrift/article/view/42244