National Research Council (U.S.). Highway Research Board. (1951). Engineering soil survey mapping: Presented at the Thirtieth Annual Meeting, 1951. Highway Research Board.
Chicago Style aipamenaNational Research Council (U.S.). Highway Research Board. Engineering Soil Survey Mapping: Presented at the Thirtieth Annual Meeting, 1951. Washington, D.C: Highway Research Board, 1951.
MLA aipamenaNational Research Council (U.S.). Highway Research Board. Engineering Soil Survey Mapping: Presented at the Thirtieth Annual Meeting, 1951. Highway Research Board, 1951.
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