Found in 3 comments on Hacker News
Rochus · 2020-11-20 · Original thread
Well, some people disagree, as usual; not really an issue; if you need a theory and formal semantics, consult the standard work: https://www.amazon.com/Theory-Objects-Monographs-Computer-Sc....
Rochus · 2020-09-20 · Original thread
You might be interesten in "A Theory of Objects" by Cardelli et al. (see https://www.amazon.com/-/de/dp/0387947752).