1. Clesceri, L.S., Greenberg, A.E., Trussel, R.R., 1989. Standard Methods for the Examination of Water and Wastewater, 17th ed. American Public Health Association, USA, 1138 p.
2. Hinkelmann, K., Kempthorne, O., 1994. Design and Analysis of Experiments, vol. I: Introduction to Experimental Design. John Wiley and Sons, USA, 495 pp.
3. Kaplan, B., 1988. Septic Systems Handbook. Lewis publisher, Michigan, USA.
4. Perkins, R., 1989. Onsite Waste Water Disposal. Lewis publisher, USA.
5. Wakatsuki, T., Omura, S., Abe, Y., Izumi, K., 1989. Treatment of domestic waste water by Multi–Soil-Layering method. Jpn. J. Soil Sci. Plant Nutr. 60, 335–351 (in Japanese).