APA (7th ed.) Citation

Chesterton, G. K. (1906). Robert Browning. Macmillan.

Chicago Style (17th ed.) Citation

Chesterton, G. K. Robert Browning. London: Macmillan, 1906.

MLA (8th ed.) Citation

Chesterton, G. K. Robert Browning. Macmillan, 1906.