APA (7th ed.) Citation

American Society for Cybernetics & Von Foerster, H. M. (1969). Purposive systems: Proceedings of the first annual symposium of the American Society for Cybernetics. Spartan Books.

Chicago Style (17th ed.) Citation

American Society for Cybernetics and Heinz M. Von Foerster. Purposive Systems: Proceedings of the First Annual Symposium of the American Society for Cybernetics. New York: Spartan Books, 1969.

MLA (9th ed.) Citation

American Society for Cybernetics and Heinz M. Von Foerster. Purposive Systems: Proceedings of the First Annual Symposium of the American Society for Cybernetics. Spartan Books, 1969.