Frisch, Thomas, Sascha Kolaric, and Dirk Schiereck. “Returns On Large Stock Price Declines And Increases In The South African Stock Market: A Note On Market Efficiency”. International Business & Economics Research Journal (IBER) 13, no. 3 (April 28, 2014): 581-592. Accessed September 4, 2020. https://clutejournals.com/index.php/IBER/article/view/8595.