These are three documents connected with the presentations by chess master Benyamin Blumenfeld and Vygotsky about the psychology of chess. The paragraph headings were added by the editors.
van der Veer, R. (2018)., Dubious moves, in E. Zavershneva & R. Van Der Veer (eds.), Vygotsky's notebooks, Dordrecht, Springer, pp. 383-389.
This document is unfortunately not available for download at the moment.