The ISBN of The Lake of Souls is 9780316154376.
The ISBN of The Merchants of Souls is 0765303302.
The ISBN of The Mirror of Simple Souls is 0809134276.
The ISBN of Paladin of Souls is 0-380-97902-0.
The ISBN of Twisted Souls is 0-7515-3523-0.
The ISBN of Lord of Souls is 978-0-345-50802-7.
The ISBN of Exiles at the Well of Souls is 0-7434-3603-2.
The ISBN of Souls in the Great Machine is 0-7653-4457-2.
The ISBN of Quest for the Well of Souls is 0-7434-7153-9.
The ISBN of Midnight at the Well of Souls is 0-7434-3522-2.
The ISBN of Twilight at the Well of Souls is 978-1-4165-0916-5.
The ISBN of Carnival of Souls - Buffy novel - is 1-4169-1182-0.
The ISBN of The Lake of Darkness is 0091408105.