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3. ASCE (1976) Subsurface investigation for design and construction of foundations of buildings. Assoc Soc Civil Eng (ASCE) Manual of Engineering Practice 79, New York
4. ASCE (1986) Use of in situ tests in geotechnical engineering. In: Proceedings In situ’86 specialty conference. Virginia Polytechnic Institute, Blacksburg, Assoc Soc Civil Eng (ASCE) geotechnical special pub. no. 6
5. ASTM (1971) Sampling of soil and rock. ASTM special technical publication (STP) 483. American Society for Testing and Materials (ASTM), Philadelphia