DjokosetiyantoD., SunarmaA., and Widanarni.. “Changes of Ammonia, Nitrite and Nitrate at Recirculation System of Red Tilapia (Oreochromis sp.) Rearing”. Jurnal Akuakultur Indonesia, Vol. 5, no. 1, Jan. 2007, pp. 13-20, doi:10.19027/jai.5.13-20.