The ISBN of The Black Circle is 978-0-545-06045-5.
The ISBN of The First Circle is 0061479012.
The ISBN of The Matarese Circle is 0399900438.
The ISBN of The Tenth Circle is 1-74114-693-3.
The ISBN of Perfect Circle - novel - is 1-931-52007-0.
The ISBN of The Closed Circle - novel - is 0-670-89254-8.
The ISBN of Elder Wisdom Circle is 978-0-452-28881-2.
The ISBN of The Black Gryphon is 0886776430.
The ISBN of Black - novel - is 1595540210.
The ISBN of Black Seconds is 1846550181.
The ISBN of Black Cocktail is 0312063040.
The ISBN of Black Rice is 2070771598.
The ISBN of The Black Crusade is 0975214306.