On the cubic law and variably saturated flow through discrete open rough-walled discontinuities

The Water Research Commission of South Africa (www.wrc.org.za) for funding of project K5/2052 [68] on Multidisciplinary Vadose Zone Hydrology, as well as project K5/2326 on Quantification of Unsaturated Flow in the Fractured Intermediate Vadose Zone by means of Geotechnical Centrifuge (to be published by the WRC in 2016).