He mentions these three schools of thought, but he wrote no separated sections for each. I learned more about Gower and Quine's views on the three schools when reading his book (what was pretty cool). But to get good distinctions I would first recommend online encyclopedias (or specialized dictionaries), my text (haha), Max Black's The Nature of Mathematics (1933), and then a few articles.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store