If you read the appendices and notes at the end of one of Cornelius Ryan's books (of which The Longest Day and A Bridge Too Far are the best known) you will learn he only included incidents where he could find two independent witnesses. He said in one afterword that he had thousands more anecdotes on his tape recorder but he would not use them as there was no 2nd source to confirm and given the stress and confusion of war he could not consider a single-sourced account to be history.

sPh