S. ALshammari, Lubna. “Studying the Distortion Impact of the Coordinates As a Result of Using the Coordinate Extension from Zone to Zone”. Journal of Engineering and Sustainable Development, vol. 16, no. 2, June 2012, pp. 161-77, https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/1208.