It’s published as an ebook, with continuous scrolling rather than pages. So any citations should be to sections of the book, not pages. The sections (and subsections) are short, so this should still make it reasonably easy to cite.
That said, the version of the book you are reading here has more capacities than the official version. As I’ll describe in more detail in the next section, there are a lot of things that the website can do that a book cannot do. Most notably, many of the tables in this version can be searched and sorted. But the Maize Books version is the official, stable, version of the book.