1 Many(possibly all) of these documents contain flaws or are incomplete, so
2 don't pull out your hair if there are inconsistencies between the documents,
3 what's in FCE Ultra, and what you observe. That's not to say that FCE Ultra
4 doesn't have its share of (emulation) flaws, though...
6 For many more NES-related documents, try http://nesdev.parodius.com