APA (7th ed.) Citation

Watstein, S. B., Calarco, P. V., & Ghaphery, J. S. (1999). Digital Library: Keywords.

Chicago Style (17th ed.) Citation

Watstein, Sarah B., Pascal V. Calarco, and James S. Ghaphery. Digital Library: Keywords. 1999.

MLA (9th ed.) Citation

Watstein, Sarah B., et al. Digital Library: Keywords. 1999.