National Portrait Gallery : : Complete Illustrated Catalogue 1856 - 1979.

MLA

Yung, K.K, and Mary Pettman. National Portrait Gallery : Complete Illustrated Catalogue 1856 - 1979. London: National Portrait Gallery (Londen), 1981.

APA

Yung, K., & Pettman, M. (1981). National Portrait Gallery : Complete Illustrated Catalogue 1856 - 1979. London: National Portrait Gallery (Londen).

Chicago

Yung, K.K., and Mary Pettman. National Portrait Gallery: Complete Illustrated Catalogue 1856 - 1979. London: National Portrait Gallery (Londen), 1981.