APA (7th ed.) Citation

British Colour Council & Wilson, R. F. (1938). Horticultural colour chart. The British Colour Council.

Chicago Style (17th ed.) Citation

British Colour Council and Robert Francis Wilson. Horticultural Colour Chart. [s.l.]: The British Colour Council, 1938.

MLA (9th ed.) Citation

British Colour Council and Robert Francis Wilson. Horticultural Colour Chart. The British Colour Council, 1938.