Lewis, W.A. (1969), &quot; Aspects of Tropical Trade 1883-1965 &quot; , The Wiksell Lectures, Estocolmo: Almqvist and Wiksell International.
Lewis, W. A. (1969), &quot; Aspects of Tropical Trade 1883-1965 &quot; , the Wiksell Lectures, Stockholm, Almqvist and Wiksell International.