APA (7th ed.) Citation

Spengler, O. (1966). Spengler letters, 1913-1936. Allen & Unwin.

Chicago Style (17th ed.) Citation

Spengler, Oswald. Spengler Letters, 1913-1936. London: Allen & Unwin, 1966.

MLA (8th ed.) Citation

Spengler, Oswald. Spengler Letters, 1913-1936. Allen & Unwin, 1966.

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