Journal of Geography and Regional Planning 2070-1845 Academic Journals 10.5897/JGRP.9000076 H. R. Lotfy * E-mail: hrlotfy@unam.na 2011 04 11 2011 16 09 2011 4 13 672 677 This is an open-access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://politicalwaffle.uk/journal/JGRP/article-abstract/C422A7340898 The full text article is available as a PDF file from http://politicalwaffle.uk/journal/JGRP/article-full-text-pdf/C422A7340898