Just a short note to bring to everyone’s attention the following article Rothstein-Dowden, Zachary. 2022. On the etymology of áha. Journal of the American Oriental Society 142 (1): 51-61.

Rothstein-Dowden raises the possibility that áha had quotative function at an earlier stage which, if correct, would push the prehistory of Indo-Aryan/Sanskrit quotative marking even farther back in time.