Hermann Zapf, as cited on the back cover of the book in version 4.0, ISBN 978-0-88179-212-6 /wiki/ISBN_(identifier)
"Can you recommend any good books on typography?". www.typography.com. Retrieved 2014-10-13. http://www.typography.com/faq/question.php?faqID=60
Foreword to version 3.1, p. 9, ISBN 0-88179-206-3 /wiki/ISBN_(identifier)