LAW 33 - SIMULTANEOUS CALLS
A call made simultaneously with one made by the player whose turn it was to call is deemed to be a subsequent call.
Related laws:
LAW 28 - CALLS CONSIDERED TO BE IN ROTATION
LAW 29 - PROCEDURE AFTER A CALL OUT OF ROTATION
LAW 30 - PASS OUT OF ROTATION
LAW 31 - BID OUT OF ROTATION
LAW 32 - DOUBLE OR REDOUBLE OUT OF ROTATION
LAW 34 - RETENTION OF RIGHT TO CALL