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Keywords from Image Description:
Hudunpaowujingzongyao. en The hu dun pao in the Wujing Zongyao Ming dynasty version of en Wujing Zongyao Immediate source Science and Civilisation in China Volume Chemistry and Chemical Technology Part Military Technology The Gunpowder Epic by Joseph Needham page Zeng Gongliang Ding Du and Yang Weide other versions PDold Wujing