Vaughan, J., & Darlington, W. (1800). The valedictory lecture delivered before the Philosophical Society of Delaware. Wilmington: Printed at the Franklin Press by J. Wilson.

Vaughan, John, and William Darlington. The Valedictory Lecture Delivered Before the Philosophical Society of Delaware. Wilmington: Printed at the Franklin Press by J. Wilson, 1800.

Vaughan, John, and William Darlington. The Valedictory Lecture Delivered Before the Philosophical Society of Delaware. Wilmington: Printed at the Franklin Press by J. Wilson, 1800.