Chanwichit, Pawinee. 2019. “The Effects of Bio-Extract and Chemical Fertilizer on Growth and Yield of Spinach (Spinacia Oleracea L.) under a Hydroponic Growing System”. Health Science, Science and Technology Reviews 12 (3):51-54. https://li01.tci-thaijo.org/index.php/journalup/article/view/201202.