1. 1) Japan Sewage Words Association : Annual Report on Sewer 2019 “Nihon-no-Gesuidō”, Japan Sewage Words Association, p. 20, 2018 (in Japanese).
2. 2) Schmidt, I., Sliekers, O., Schmid, M., Bock, E., Fuerst, J., Kuenen, J. G., Jetten, M. S. M. and Strous, M. : New concept of microbial treatment process for the nitrogen removal in wastewater, FEMS Microbiology Reviews, Vol. 27, No. 4, pp. 481-492, 2003.
3. 3) Mudrack, K. and Kunst, S. : Biologie der Abwasser- reinigung, Springer Spektrum, pp. 57-161, 2010 (in German).
4. 4) Ministry of Land, Infrastructure, Transport and Tourism : Standard Sewer Regulations, Koku-Sui-Ge, 53, 2015 (in Japanese).
5. 5) Ministry of Land, Infrastructure, Transport and Tourism : Sewerage Act, No. 79 of April 24, 1958, Amendment of Act, No. 69 of 2014 (in Japanese).