APA
Cumberledge G., Hoffman G., . (1976). Fundamentals of frost action in subgrade soils. Harrisburg, PA: Pennsylvania Department of Transportation. Bureau of Materials, Testing and Research. Technical Research nr 68-13.
Chicago
Cumberledge G, Hoffman GL, . 1976. Fundamentals of frost action in subgrade soils. Harrisburg, PA: Pennsylvania Department of Transportation. Bureau of Materials, Testing and Research. Technical Research nr 68-13.
Harvard
Cumberledge G., Hoffman G., . (1976). Fundamentals of frost action in subgrade soils. Harrisburg, PA: Pennsylvania Department of Transportation. Bureau of Materials, Testing and Research. Technical Research nr 68-13.
MLA
Cumberledge G, Hoffman GL, . Fundamentals of frost action in subgrade soils. Harrisburg, PA: Pennsylvania Department of Transportation. Bureau of Materials, Testing and Research. Technical Research nr 68-13. 1976.