Yousif, H.M. <https://pure.iiasa.ac.at/view/iiasa/1674.html> ORCID: https://orcid.org/0000-0001-8071-1395 <https://orcid.org/0000-0001-8071-1395>  (1995).  Rural population settlements and the environment in central Sudan.    In:  Population-Environment-Development Interactions. Eds. Clarke, J.I. & Tabah, L.,  Paris: CICRED.