American Association of State Highway and Transportation Officials (AASHTO). (2012). Standard specifications for transportation materials and methods of sampling and testing: Specifications. Part 1A (32 edición.). Washintong, D.C, Estados Unidos: AASHTO.
Chicago Style CitationAmerican Association of State Highway and Transportation Officials (AASHTO). Standard Specifications for Transportation Materials and Methods of Sampling and Testing: Specifications. Part 1A. 32 edición. Washintong, D.C, Estados Unidos: AASHTO, 2012.
MLA CitationAmerican Association of State Highway and Transportation Officials (AASHTO). Standard Specifications for Transportation Materials and Methods of Sampling and Testing: Specifications. Part 1A. 32 edición. Washintong, D.C, Estados Unidos: AASHTO, 2012.