Field study in American geography; the development of theory and method exemplified by selections. Platt, Robert S. (Robert Swanton), 1891-1964, ed. Geography Study and teaching United States. H31 .C514 no. 61 910 PLF Chicago, 1959. 1959. 1959 Text 405 p. : eng University of Chicago. Dept. of Geography. Research paper no. 61 United States.