Quantification of oxalate ions and protons released by ectomycorrhizal fungi in rhizosphere soil Casarin, Valter ; Plassard, Claude ; Souche, Gérard ; Arvieu, Jean-Claude Abstract Publication: Agronomy for Sustainable Development Pub Date: July 2003 DOI: 10.1051/agro:2003020 Bibcode: 2003AgSD...23..461C