| 1 | [1] El-Rabbany A., 2006. Introduction to GPS: The Global Positioning System, Second Edition, Artech House, pp. 159-160 |
| 2 | [2] Hoffmann-Wellenhof, B., Lichtenegger H., and Collins J., 2001. GPS Theory and Practice 5th revised edition, Springer-Verlag Wien-New York, 382 pages |
| 3 | [3] Wolf, P. R., Ghilani, C. D. 2002. Elementary Surveying, An Introduction to Geomatics, 10th Edition, Prentice Hall Upper Saddle River, New Jersey, 887 pages |