APA (7th ed.) Citation

Knight, D. M., & Humboldt, A. v. (2004). Scientific travellers, 1790-1877. Routledge.

Chicago Style (17th ed.) Citation

Knight, David M., and Alexander von Humboldt. Scientific Travellers, 1790-1877. London ; New York: Routledge, 2004.

MLA (9th ed.) Citation

Knight, David M., and Alexander von Humboldt. Scientific Travellers, 1790-1877. Routledge, 2004.