APA (7th ed.) Citation

De Terra, H. (1979). Humboldt : the life and times of Alexander von Humboldt, 1769-1859: The life and times of Alexander von Humboldt, 1769-1859. Octagon Books.

Chicago Style (17th ed.) Citation

De Terra, Helmut. Humboldt : The Life and Times of Alexander Von Humboldt, 1769-1859: The Life and Times of Alexander Von Humboldt, 1769-1859. New York: Octagon Books, 1979.

MLA (9th ed.) Citation

De Terra, Helmut. Humboldt : The Life and Times of Alexander Von Humboldt, 1769-1859: The Life and Times of Alexander Von Humboldt, 1769-1859. Octagon Books, 1979.

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