Thi Tuan Anh, Tran. “Applying Approximate Entropy to Compare the Randomness of Data Series in Aseans’stock Markets”. Science & Technology Development Journal - Economics - Law and Management 2, no. 4 (March 28, 2019): 5-13. Accessed November 12, 2019. http://stdjelm.scienceandtechnology.com.vn/index.php/stdjelm/article/view/525.