APA (7th ed.) Citation

Punshon, E. R. (1949). So many doors. Gollancz.

Chicago Style (17th ed.) Citation

Punshon, E. R. So Many Doors. London: Gollancz, 1949.

MLA (8th ed.) Citation

Punshon, E. R. So Many Doors. Gollancz, 1949.