(1988):
The Atlas System of Morocco,
Paperback, Springer Verlag; (May 1988), ISBN: 3540190864 amazon.com
Bernard J. Smith (1977):
Four Geomorphological Studies of Morocco and the Northwest Sahara,
Hardcover: 60 pages, Department of Geography University of Reading; (January 1977), ISBN: 0704904632 amazon.com
Volker H. Jacobshagen ed. (1988):
The Atlas System of Morocco: Studies on Its Geodynamic Evolution,
Lecture Notes in Earth Sciences, Vol 15
Paperback: 499 pages, Springer Verlag; (June 1988) amazon.com
Jean Gattefossé (1934):
Les grottes au Maroc. — De l’habitat primitif au lieu cultuel,
Revue d'Écologie (La Terre et La Vie) Year 1934 4-1 pp. 33-45.
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