Gnommish letter chart
Centaurean letter chart
Eternity code letter chart

Artemis Fowl (Gnommish)
The Arctic Incident (Centaurean)
The Eternity Code (unnamed)
The Opal Deception (Gnommish)
The Lost Colony (Gnommish)
The Artemis Fowl Files (Gnommish)
Artemis Fowl : UK relaunch (Gnommish)
The Arctic Incident : UK relaunch (Gnommish)
The Eternity Code : UK relaunch (Gnommish)
The Opal Deception : UK relaunch (Gnommish)