Laws of Cricket 1947 Code (Fourth Edition) - Law 41
Either Batsman is out "Run out" - If in running or at any time, while the ball is in play, he be out of his ground, and his wicket be put down by the opposite side. If the batsmen have crossed each other, he that runs for the wicket which is put down is out; if they have not crossed he that has left the wicket which is put down is out. But unless he attempt to run, the Striker shall not be given "Run out" in the circumstances stated in Law 42, even should "No Ball" have been called.
Note on Law 41
1. If the ball is played on to the opposite wicket, neither batsman is liable to be "Run out" unless the ball has been touched by a fieldsman before the wicket is put down.
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