APA (7th ed.) Citation

Say, T., & De La Beche, H. T. (1826). On two genera and several species of Crinoidea. W. Phillips.

Chicago Style (17th ed.) Citation

Say, Thomas, and Henry T. De La Beche. On Two Genera and Several Species of Crinoidea. London: W. Phillips, 1826.

MLA (8th ed.) Citation

Say, Thomas, and Henry T. De La Beche. On Two Genera and Several Species of Crinoidea. W. Phillips, 1826.