APA (7th ed.) Citation

Jordan, R. R., & Groot, J. J. (1962). Some observations on the sediments of the Delaware River south of Wilmington. [publisher not identified].

Chicago Style (17th ed.) Citation

Jordan, Robert R., and Johan J. Groot. Some Observations on the Sediments of the Delaware River South of Wilmington. [Newark, Del.]: [publisher not identified], 1962.

MLA (9th ed.) Citation

Jordan, Robert R., and Johan J. Groot. Some Observations on the Sediments of the Delaware River South of Wilmington. [publisher not identified], 1962.