APA (7th ed.) Citation

Hoppe, E. O. (1931). The fifth continent. Simpkin, Marshall.

Chicago Style (17th ed.) Citation

Hoppe, E. O. The Fifth Continent. London: Simpkin, Marshall, 1931.

MLA (9th ed.) Citation

Hoppe, E. O. The Fifth Continent. Simpkin, Marshall, 1931.

Warning: These citations may not always be 100% accurate.