don’t recall, it covered both bitcoin and etherium and investigated who owned what. ill see if i can’t find it. edit: this seems to be the academic version of it, but theres a prettier journalism version with more stories and pictures: https://arxiv.org/abs/2206.02871

in this case i seem to have misremembered owners vs miners, but I’ll keep poking around. this one is also older than i remember.