The ISBN of The Crystal City is 0-312-86483-3.
The ISBN of The Crystal Cave is 0688013988.
The ISBN of The Seventh Crystal is 0440410517.
The ISBN of The Crystal Frontier is 978-0156006200.
The ISBN of Crystal Singer is 0-727-82022-2.
The ISBN of Crystal Express is 0-87054-158-7.
The ISBN of Crystal Rain is 0-7653-1227-3.
The ISBN of Nor Crystal Tears is 0-345-29141-7.
The ISBN of The City in History is 0156180359.
The ISBN of Strumpet City is 0099187507.
The ISBN of Zoo City is 9781770098183.
The ISBN of City of Joy is 0099140918.
The ISBN of Astro City is 9781401228439.