Geological structures and maps : a course in interpretation with applications for civil & mining engineers / A. Roberts. Roberts, Albert F., 1911- Geology Maps. Geology, Structural. QE33 .R6 1958 551.1 ROG London ; New York : Cleaver-Hume Press ; Macmillan, 1958 (1971 printing). 1958 (1971 printing). 1958 Text viii, 92 p. : eng