1. (1976). ‘Use of aerial photographs in erosion reconnaissance survey and local detailed studies in the Mérida province, Spain’, Thesis for MSc, International Institute for Aerial Survey and Earth Sciences (ITC).
2. , and , (1972). Soil Physics, 4th edn, Wiley, 146.
3. (1978). ‘Reconnaissance survey of erosion hazard near Mérida, Spain’, Proc. Workshop Assessment of erosion in USA and Europe, University of Ghent.
4. and (1976). ‘Het verband tussen textuur en aggregaatstabiliteit’, Internal report, Laboratory for Physical Geography and Soil Science, University of Amsterdam.
5. The development, use and efficiency of indices of soil erodibility