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2. T. Sherriff. Strength Losses in Cores: A Laboratory Investigation Using Cylinders, TR69, R.M.C., Egham (1971).
3. The Relationship Between the Strength and Standard Cubes;Murphy,1973
4. Estimation of Concrete Cube Strength from Cores - A Laboratory Study Using Moulded Cylinders;Sangha,1973
5. European Concrete Committee (CEB). Recommendations for an International Code of Practice for Reinforced Concrete, Cem. Concr., London (1963).