APA (7th ed.) Citation

Havinga, A., & Langer, N. (2015). Invisible languages in the nineteenth century. Peter Lang.

Chicago Style (17th ed.) Citation

Havinga, Anna, and Nils Langer. Invisible Languages in the Nineteenth Century. Oxford, [England]: Peter Lang, 2015.

MLA (9th ed.) Citation

Havinga, Anna, and Nils Langer. Invisible Languages in the Nineteenth Century. Peter Lang, 2015.