= Intel manual
Although it is impossible to understand without examples in mind, try to get familiar with the manuals as soon as possible.
Intel describes paging in the https://web.archive.org/web/20151025081259/http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-system-programming-manual-325384.pdf[Intel Manual Volume 3 System Programming Guide - 325384-056US September 2015] Chapter 4 "Paging".
Specially interesting is Figure 4-4 "Formats of CR3 and Paging-Structure Entries with 32-Bit Paging", which gives the key data structures.