APA (7th ed.) Citation

Walpole, H. (1941). Open letter of an optimist. London: Macmillan & co.

Chicago Style (17th ed.) Citation

Walpole, Hugh. Open Letter of an Optimist. London: Macmillan & co, 1941.

MLA (8th ed.) Citation

Walpole, Hugh. Open Letter of an Optimist. London: Macmillan & co, 1941.

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