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2. Kierkegaard-Hansen, P., ‘Lok-strength,’Nordish Betong (Stockholm) 19 (3) (1975) 19–28.
3. Malhotra, V. M., ‘Evaluation of the pullout test to determine strength of in-situ concrete,’Mater. Struct. 8 (43) (1975) 19–31.
4. ASTM STP;O. Richards,1977
5. SP-45;T. Rutenbeck,1974