00620cam a22002051 4500 agr41000451 DLC 20260227111000.0 770505s1940 enka 001 0 eng c agr41000451 (OCoLC)2944036 U.. Dept of Agr. Libr ABAU ABAU DLC HC55 .C55 330.904 Clark, Colin, 1905- The conditions of economic progress, by Colin Clark. London, Macmillan and co., limited, 1940. xii, 504 p. tables (part fold.) diagrs. (1 fold.) 22 cm. Economic history. 10133 10133