Guangchuan shuba 廣川書跋 "Notes on calligraphies from Broad River [Studio]" is a book collecting critics of calligraphy compiled during the late Northern Song period 北宋 (960-1126) by Dong You 董逌 (early 12th cent.), courtesy name Yanyuan 彥遠, from Dongping 東平 (today in Shandong). He was academician awaiting instructions (daizhi 待制) in the Huiyou Hall 徽猷閣 and wrote a sister-book, Guangchuan huaba 廣川畫跋 on painting, a book on library, Guangchuan cangshu zhi 廣川藏書志, and comments on poetry, Guangchuan Shigu 廣川詩故. Politically, Dong You seems to have been involved in the puppet regime of Zhang Bangchang 張邦昌 (1081-1127).
The book of 10 juan length was written after Dong You had fled to south China and lost the whole collection of antiques that his family had collected over decades. Dong therefore assembled what he knew about calligraphic inscriptions on antique collectibles and rubbings of stele inscriptions. Most of the latter date from the Han 漢 (206 BCE-220 CE) to Tang 唐 (618-907) periods, and only a few had been written by subjects of the Song dynasty. The first three juan refer to inscriptions on bells, bronze vessels and weapons from antiquity, including the famous Zu Chu wen 詛楚文 and the rock inscription Yishan ming 嶧山銘.
The fourth fascicle presents notes on inscriptions from the Qin period 秦 (221-206 BCE). Inscriptions on steles and rubbings of the Stone Classics are the object of chapter 5. Calligraphic objects from the Southern and Northern Dynasties period 南北朝 (300~600) include rubbings of the most famous art objects, like the "Preface of Orchid Pavilion" (Lanting xu 蘭亭序), Wang Yishao's 王逸少 (i.e. Wang Xizhi 王羲之, 303-361) Shiqi tie 十七帖 or Monk Zhiyong's 智永 (6th cent.) Zhen-cao qianzi wen 真草千字文 (see Qianziwen 千字文). Other famous calligraphies were produced by Zhong Yao 鍾繇 (151-230), Huang Xiang 皇象 (3rd cent.) and Wang Xianzhi 王獻之 (344-386). As to Tang-period art, Dong You praises the works of Ouyang Xun 歐陽詢 (557-641), Yu Shinan 虞世南 (558-638), Chu Suiliang 褚遂良 (596-658), Xue Ji 薛稷 (649-713), Yan Zhenqing 顏真卿 (709-785), Liu Gongquan 柳公權 (778-865), Zhang Xu 張旭 (c. 675-c. 750) and the monk Huaisu 懷素 (725-785).
Each entry includes notes and a brief biography of the particular artist, and also notes on the provenance of the art object, including a discussion about its authenticity. For the inscription Sun Quan'ao bei 孫叔敖碑, for instance, Dong remarks that during the Han period, people had not sufficient expertise to tell originals from forgeries, and thus transmitted wrong attributions.