Minecraft wiki entry for Player.dat_format, associated text: 1 NBT structure
2 Item structure
2.1 General Tags
2.2 Attribute Modifiers
2.3 Block Tags
2.4 Display Properties
2.5 Enchantments
2.6 Potion Effects
2.7 Armor Stands, Spawn Eggs and Item Frames
2.8 Book and Quills
2.9 Written Books
2.10 Buckets of Aquatic Mob
2.11 Bundle
2.12 Compasses
2.13 Crossbows
2.14 Debug Sticks
2.15 Firework Rockets
2.16 Firework Stars
2.17 Maps
2.18 Player Heads
2.19 Suspicious Stew
3 Inventory slot numbers
4 History
5 References