The ISBN of The Crystal Frontier is 978-0156006200.
The ISBN of The Other Side of the Frontier is 0868408921.
The ISBN of The Crystal Cave is 0688013988.
The ISBN of The Seventh Crystal is 0440410517.
The ISBN of Greenhorn on the Frontier is 0-7232-6104-0.
The Crystal Frontier was created in 1995.
The ISBN of Crystal Singer is 0-727-82022-2.
The ISBN of The Crystal City is 0-312-86483-3.
The ISBN of Crystal Express is 0-87054-158-7.
The ISBN of Crystal Rain is 0-7653-1227-3.
The Crystal Frontier has 280 pages.
The ISBN of Nor Crystal Tears is 0-345-29141-7.
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