Pikkarainen, Eetu. “Adaptation, Learning, Bildung: Discussion With Edu- and Biosemiotics”. Sign Systems Studies 46, no. 4 (December 31, 2018): 435-451. Accessed May 6, 2021. https://ojs.utlib.ee/index.php/sss/article/view/SSS.2018.46.4.02.