(To make sure this artbook just doesn't have Atelier artwork, it also has Mana Khemia, which is another series Gust has developed, for those who don't know)

This book contains artwork from:
Atelier Marie: The Alchemist of Salburg
Atelier Ellie: The Alchemist of Salburg 2
Atelier Lilie: The Alchemist of Salburg 3
Atelier Judie: The Alchemist of Gramnad
Atelier Violet: The Alchemist of Gramnad 2
Atelier Iris: Eternal Mana
Atelier Iris: Eternal Mana 2
Atelier Iris 3: Grand Phantasm
Mana Khemia: Alchemists of Al-Revis
Mana Khemia 2: Fall of Alchemy
Atelier Rorona: Alchemist of Arland
(I have played Gust games, but wasn't too familiar with the Atelier games not published by NISA) Also this was taken from the Official Udon website
I hope this helps...