APA (7th ed.) Citation

Snell, J. R. (1990). Knowledge-based navigation in a hypertext network. [publisher not identified].

Chicago Style (17th ed.) Citation

Snell, James Robert. Knowledge-based Navigation in a Hypertext Network. [Place of publication not identified]: [publisher not identified], 1990.

MLA (9th ed.) Citation

Snell, James Robert. Knowledge-based Navigation in a Hypertext Network. [publisher not identified], 1990.