APA Edition Citation

Clausen, J. (1951). Stages in the evolution of plant species. Hafner Publishing Compnay.

Chicago Edition Citation

Clausen, Jens. Stages in the Evolution of Plant Species. Newyork: Hafner Publishing Compnay, 1951.

MLA Edition Citation

Clausen, Jens. Stages in the Evolution of Plant Species. Hafner Publishing Compnay, 1951.

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