The Chanzi 纏子 "Master Chan" is a Mohist treatise written by an unknown author during the Warring States period 戰國 (5th cent.-221 BCE). The book is not listed in the imperial biographies of the official histories Hanshu 漢書 and Suishu 隋書 but is first mentioned during the Tang 唐 (618-907) and Song 宋 (960-1279) periods. The surviving fragments can not clearly be attributed to the Chanzi or another Mohist treatise, the Dongzi 董子. It is even not certain if the two books were not one and the same in reality. The Qing period 清 (1644-1911) scholar Ma Guohan 馬國翰 therefore put them side by side in his fragment collection Yuhan shanfang yiji shu 玉函山房輯佚書, the Chanzi as a Mohist treatise, the Dongzi as a Confucian treatise.
Source: Li Xueqin 李學勤, Lü Wenyu 呂文鬰 (1996). Siku da cidian 四庫大辭典, vol. 2, p. 1874. Changchun: Jilin daxue chubanshe.