Estall, R. C., & Buchanan, R. O. (1973). Industrial activity and economic geography: A study of the forces behind the geographical location of productive activity in manufacturing industry (3rd [revised] ed.). Hutchinson.

Estall, Robert C., and R. Ogilvie Buchanan. Industrial Activity and Economic Geography: A Study of the Forces Behind the Geographical Location of Productive Activity in Manufacturing Industry. 3rd [revised] ed. London: Hutchinson, 1973.

Estall, Robert C., and R. Ogilvie Buchanan. Industrial Activity and Economic Geography: A Study of the Forces Behind the Geographical Location of Productive Activity in Manufacturing Industry. 3rd [revised] ed. Hutchinson, 1973.