Valsiner, Jaan. “The Semiotic Construction of Solitude: Processes of Internalization and Externalization”. Sign Systems Studies 34, no. 1 (December 31, 2006): 9-35. Accessed October 25, 2021. https://ojs.utlib.ee/index.php/sss/article/view/SSS.2006.34.1.01.