Camargo, Ângelo P. de, Grohmann, F. and Camargo, M. B. P. de (2014) “An inexpensive direct reading tensiometer”, Pesquisa Agropecuaria Brasileira, 17(12), pp. 1763–1772. doi: 10.1590/S1678-3921.pab1982.v17.16420.