Pattee, Howard H., and Kalevi Kull. “A Biosemiotic Conversation: Between Physics and Semiotics”. Sign Systems Studies 37, no. 1/2 (December 15, 2009): 311-331. Accessed September 20, 2021. https://ojs.utlib.ee/index.php/sss/article/view/SSS.2009.37.1-2.12.