A Guide to the National Gallery (London) / / Homan Potterton ; with a Foreword by Michael Levey.

MLA

Potterton, Homan, and Michael Levey. A Guide to the National Gallery (london). London: National Gallery (Londen), .d.

APA

Potterton, H., & Levey, M. (.d). A Guide to the National Gallery (London). London: National Gallery (Londen).

Chicago

Potterton, Homan, and Michael Levey. A Guide to the National Gallery (london). London: National Gallery (Londen), .d.