You might find this book from your local library.
The Rape of Nanking: The Forgotten Holocaust of World by Iris Chang, page200
I became terrified that the history of three hundred thousand murdered Chinese might disappear just as they themselves had disappeared under Japanese occupation and that the world might actually one day believe the Japanese politicians who have insisted that the Rape of Nanking was a hoax and a fabrication--that the massacre never happened at all. By writing this book, I forced myself to delve into not only history but historiography--to examine the forces of history and the process by which history is made. What keeps certain events in history and assigns the rest to oblivion? Exactly how does an event like the Rape of Nanking vanish from Japan's (and even the world's) collective memory?"