Once or twice James Joyce dictated a bit of Finnegans Wake to Samuel Beckett, though dictation did not work very well for him. In the middle of one session there was a knock at the door which Beckett didn't hear.
Joyce said, "Come in," and Beckett naturally wrote it down.
Later, reading back what he had written, Joyce said: "What's that? 'Come in'?"
"Yes, you said that," Beckett replied.
Joyce thought for a moment, then said "Let it stand."
Joyce in Zürich, c. 1918