1. Division of Soil Hydrology; Georg-August Univ. of Göttingen; Göttingen Germany
2. Dep. of Agricultural Engineering; Univ. of Khartoum; Khartoum Sudan
3. Group of Geophysics; Univ. of Koblenz-Landau; Landau Germany
4. Aquatrols Corporation of America; Paulsboro NJ 08066
5. Lab. for Neutron Scattering and Imaging; Paul Scherrer Institute; Villigen Switzerland