Suhardiyanto, H., Arif, C. and Setiawan, B. I. (2013) “Optimization of EC Values of Nutrient Solution for Tomato Fruits Quality in Hydroponics System Using Artificial Neural Network and Genetic Algorithms”, Journal of Mathematical and Fundamental Sciences, 41(1), pp. 38-49. doi: 10.5614/itbj.sci.2009.41.1.3.