Micropropagation of walnut trees (Juglans regia L) and response to arbuscular mycorrhizal inoculation R. Dolcet-Sanjuan, E. Claveria, A. Camprubí, V. Estaún and C. Calvet Agronomie, 16 10 (1996) 639-645 DOI: 10.1051/agro:19961008