The Japanese and English translations of the Chinese book, A History of the Nanjing Massacre, will help more foreigners know about one of the darkest chapters in 20th-century history.

Recently published by Nanjing University Press, the two books have been translated from the 2014 Chinese version that was written by Zhang Xianwen, a history professor at Nanjing University, in East China's Jiangsu province, and other Chinese historians.

Zhang spent a decade rummaging through relevant historical files around the world, ranging from the US Library of Congress to the national archives in Germany, Japan and the United Kingdom, as well as top academic institutions in Taiwan. Archived government documents, newspaper reports, personal stories of survivors and other sources formed the basis of the book.