APA (7th ed.) Citation

Lear, T., Ellicott, A., Thackara, J., & Vallance, J. Observations on the river Potomack, the country adjacent, and the city of Washington.

Chicago Style (17th ed.) Citation

Lear, Tobias, Andrew Ellicott, James Thackara, and J. Vallance. Observations on the River Potomack, the Country Adjacent, and the City of Washington.

MLA (9th ed.) Citation

Lear, Tobias, et al. Observations on the River Potomack, the Country Adjacent, and the City of Washington.