APA
Portsmouth Polytechnic Department of Surveying, . (1974). Acceptable levels of risk. London: Standard Method of Measurement Development Unit.
Chicago
Portsmouth Polytechnic Department of Surveying, . 1974. Acceptable levels of risk. London: Standard Method of Measurement Development Unit.
Harvard
Portsmouth Polytechnic Department of Surveying, . (1974). Acceptable levels of risk. London: Standard Method of Measurement Development Unit.
MLA
Portsmouth Polytechnic Department of Surveying, . Acceptable levels of risk. London: Standard Method of Measurement Development Unit. 1974.