APA (7th ed.) Citation

Roberts, C. G. D. The Watchers of the Trails: A Book of Animal Life.

Chicago Style (17th ed.) Citation

Roberts, Charles G. D. The Watchers of the Trails: A Book of Animal Life.

MLA (9th ed.) Citation

Roberts, Charles G. D. The Watchers of the Trails: A Book of Animal Life.

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