The score is tied at the end of regulation time. During the overtime period, the official scorer informs the referee that Team A had an additional point in the fourth quarter that was not counted. In (a), the referee reviews the scorebook and recognizes where a point was not properly credited to Team A; or (b) the referee does not have definite knowledge that a point was not credited to Team A.
In (a), the referee adds a point to Team A’s score. In (b), the referee does not add a point to Team A’s score. In either case, the referee continues the overtime period to completion.