That is the correct reference. I don’t know if I’d say the similarities are only superficial however. The blog post on super-inductive types seems to bear out at least a strong isomorphism modulo syntax.

Agreed: I meant that there were superficial similarities, not merely superficial similarities. Here's the original paper (I think?) on self types; maybe there's an obvious link in there.

https://homepage.divms.uiowa.edu/~astump/papers/fu-stump-rta...