APA (7th ed.) Citation

Butterworth, E. A. S. (1970). The Tree at the Navel of the Earth.

Chicago Style (17th ed.) Citation

Butterworth, E. A. S. The Tree at the Navel of the Earth. Berlin, 1970.

MLA (8th ed.) Citation

Butterworth, E. A. S. The Tree at the Navel of the Earth. 1970.

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