- gameboy homebrew - Gameboy Homebrew Development (David Schamber).
- How to make a (GameBoy) emulator? by Petar Veličković, University of Cambridge.
- New Down and Dirty Gameboy VRAM Timing Document + Test ROM by Kevtris.
- Open Game Boy Documentation Project - WIP documentation effort. Similar to Pan Docs but corrected and in a single page.
- Game Boy CPU Manual - Assembly language commands, timings and opcodes. Has some inaccuracies and errors.
- GBZ80 to items - An online converter, translates Game Boy assembly into Pokémon R/B/Y items (Source).