APA

Gould P., Kinsey P., . (1981). Variable direction signs to car parks. London: Department of the Environment.

Chicago

Gould P, Kinsey PJ, . 1981. Variable direction signs to car parks. London: Department of the Environment.

Harvard

Gould P., Kinsey P., . (1981). Variable direction signs to car parks. London: Department of the Environment.

MLA

Gould P, Kinsey PJ, . Variable direction signs to car parks. London: Department of the Environment. 1981.