[1] Abd El-Daiem, S. (2011). Water Quality Management in Egypt. Journal of Water Resources Development, 27, 181-202.
https://doi.org/10.1080/07900627.2010.531522
[2] Adekunle, L., Adetunji, M., & Gbadebo, A. (2007). Assessment of Ground Water Quality in a Typical Rural Settlement in South Nigeria. International Journal of Environmental Research and Public Health, 4, 307-318.
https://doi.org/10.3390/ijerph200704040007
[3] Akume, D., & Weber, G.-W. (2002). Cluster Algorithms: Theory and Methods. Journal of Computational Technologies, 7, 15-27.
[4] Cattel, R. D. (1966). The Scree Test for the Number of Factors. Multivariate Behavioral Research, 1, 245-276.
https://doi.org/10.1207/s15327906mbr0102_10
[5] CDWC (2018). Central Laboratory Annual Technical Report. Cairo Drinking Water Company.
[6] Chatfield, C., & Collin, A. J. (1980). Introduction to Multivariate Analysis. New York: Chapman and Hall in Association with Methuen, Inc.
https://doi.org/10.1007/978-1-4899-3184-9
[7] Davis, J. C. (2002). Statistics and Data Analysis in Geology (3rd ed.). New York: John Wiley and Sons, Inc.
[8] Egyptian Governmental Law No. 48 (1982). The Implementer Regulations for Law 48/1982 Regarding the Protection of the River Nile and Water Ways from Pollution (pp. 12-35). Map. Periodical Bulletin, 3-4 December.
[9] EWQS (Egyptian Drinking Water Quality Standards) (2007). Ministry of Health, Population Decision Number 458.
[10] Goher, M. E., Hassan, A. M., Abdel-Moniem, I. A., Fahmy, A. H., & El-Sayed, S. M. (2014). Evaluation of Surface Water Quality and Heavy Metal Indices of Ismailia Canal, Nile River, Egypt. Egyptian Journal of Aquatic Research, 40, 225-233.
https://doi.org/10.1016/j.ejar.2014.09.001
[11] Jolliffe, I. T. (2002). Principal Component Analysis (2nd ed.). New York: Springer-Verlag.
[12] Karavoltsos, S., Sakellar, A., Mihopoulos, N., Dassenakis, M., & Scoullos, M. J. (2008). Evaluation of the Quality of Drinking Water in Regions of Greece. Desalination, 224, 317-329.
https://doi.org/10.1016/j.desal.2007.06.013
[13] Kaufman, L., & Rousseeuw, P. J. (1990). Finding Groups in Data—An Introduction to Cluster Analysis. New York: John Wiley & Sons Inc.
https://doi.org/10.1002/9780470316801
[14] Panda, U. C., Sundaray, S. K., Rath, P., Nayak, B. B., & Bhatta, D. (2006). Application of Factor and Cluster Analysis for Characterization of River and Estuarine Water Systems—A Case Study: Mahanadi River (India). Journal of Hydrology, 331, 434-445.
https://doi.org/10.1016/j.jhydrol.2006.05.029
[15] Reghunath, R., Murthy, S. T. R., & Raghavan, B. R. (2002). The Utility of Multivariate Statistical Techniques in Hydrogeochemical Studies. An Example from Karnataka, India. Water Research, 36, 2437-2442.
https://doi.org/10.1016/S0043-1354(01)00490-0
[16] Saleh, A. R. (2009). Bacteria and Viruses in the Nile. Monographiae Biologicae, 89, 407-429.
https://doi.org/10.1007/978-1-4020-9726-3_20
[17] Selim, S. Z. (1984). Soft Clustering of Multi-Dimensional Data: A Semi-Fuzzy Approach. Pattern Recognition, 17, 559-568.
https://doi.org/10.1016/0031-3203(84)90054-2
[18] Suhr, D. (2005). Principal Component Analysis vs. Exploratory Factor Analysis. SUGI 30 Proceedings.
http://www2.sas.com/proceedings/sugi30/Leadrs30.pdf
[19] Tebbutt, T. (1998). Principles of Water Quality Control (5th ed.). Sheffield: Hallam University.
[20] Terceiro, P., Lobo-Ferreira, J. P., & Leitão, T. E. (2008). Análise da qualidade da água e questões de governan-ciana Albufeirado Alqueva. Comunicaçãoapresen-tada no 9o Congresso da água-água: Desafios de hoje, exigências de amanhã. Cascais, Portugal. (In Portuguese)
http://www.aprh.pt/congressoagua2008/PDF/Lobo-FerreiraAlqueva.pdf
[21] Toufeek, M. A., & Korium, M. A. (2009). Quality in Lake Nasser Water. Global Journal of Environmental Research, 3, 141-148.
[22] Trauwaert, E., Kaufman, L., & Rousseeuw, P. (1991). Fuzzy Clustering Algorithms Based on the Maximum Likelihood Principle. Fuzzy Sets and Systems, 42, 213-227.
https://doi.org/10.1016/0165-0114(91)90147-I
[23] Yu, S., Shang, J., Zhao, J., & Guo, H. (2003). Factor Analysis and Dynamics of Water Quality of the Songhua River Northeast China. Water, Air, & Soil Pollution, 144, 159-169.
https://doi.org/10.1023/A:1022960300693
[24] Zamxaka, M., Pironcheva, G., & Muyima, N. Y. O. (2004). Microbiological and Physico-Chemical Assessment of the Quality of Domestic Water Sources in Selected Rural Communities of the Eastern Cape Province, South Africa. Water SA, 30, 333-340.
https://doi.org/10.4314/wsa.v30i3.5081
[25] Zeng, X., & Rasmussen, T. C. (2005). Multivariate Statistical Characterization of Water Quality in Lake Lanier, Georgia, USA. Journal of Environmental Quality, 34, 1980-1991.
https://doi.org/10.2134/jeq2004.0337