Martins, M. A. and Read, D. J. (1997) “The effects of disturbance on the external mycelium of arbuscular mycorrhizal fungi on plant growth”, Pesquisa Agropecuaria Brasileira, 32(11), pp. 1183–1189. doi: 10.1590/S1678-3921.pab1997.v32.4769.