Since the work of Lev S. Vygotsky (Russian psychologist, 1896-1934) is, on the one hand, extremely important for understanding autism, on the other hand, very extensive, and unfortunately little known and only poorly available, you can find excerpts from essential texts here:
https://autismusberatung.info/vygotskij-lev-s/
Both in the original versions of the English editions and some as translations into German.
