Zhang, Xin, Dongxian He, Genhua Niu, Zhengnan Yan, and Jinxiu Song. 2018. “Effects of Environment Lighting on the Growth, Photosynthesis, and Quality of Hydroponic Lettuce in a Plant Factory”. International Journal of Agricultural and Biological Engineering 11 (2):33-40. https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/3420.