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Continue to ChatIS : 5640 - 1970 (Reaffirmed 1998 ) https://civilengineer.co.in/indian-standard-codes/download-free-is-5640-1970-reaffirmed-1998-civil-engineer/attachment/5640/
IS : 5640 - 1970 (Reaffirmed 1998 ) https://civilengineer.co.in/indian-standard-codes/download-free-is-5640-1970-reaffirmed-1998-civil-engineer/attachment/5640/