Humus und humusdüngung /

by Scheffer, Fritz
Published 1960

Die humusstoffe des bodens: Ergebnisse und probleme der humusforschung /

by Kononowa, M. M.
Published 1958

Humic substances in soil and crop sciences: Selected readings : Proceedings of a symposium cosponsored by the International Humic Substances Society; divisions S-3, S-2, S-4, S-5,...

Published 1990