It got me at Belter civilization apparently being already a well-established sci-fi trope half a decade ago. And here I thought The Expanse was the first to dive deep into this idea. I need to seriously catch up with sci-fi stories from before 1980s.
Also nice that, before completely ruining the idea of the Belters, and apparently also having "science robbing sf writers of Mars and Venus" (presumably in earlier installments of this work?), he proposed a working model for independent civilization settling Jovian moons. I wonder if there's an updated version of the table somewhere, with the numbers reflecting current knowledge of the Jovian area and space propulsion.