The Yanpu 硯譜 "Notes on inkslabs" is a very small book on inkslabs written by an unknown person during the Song period 宋 (960-1279). In its earliest form in the collectaneum Baichuan xuehai 百川學海, not even a year is mentioned. The 32 paragraphs are a loose collection of miscellaneous statements about inkslabs, their place of origin and how they were used by famous masters like Ouyang Xiu 歐陽修, Su Shi 蘇軾, Tang Xun 唐詢 or Zheng Qiao 鄭樵. Even in these few lines, a lot of errors are included, like the jade inkslab by Xu Hanyang 許漢陽 which is a story from Master Gushenzi's 谷神子 Boyiji 博異記, in which the stone belongs to the Dragon Maid 龍女 and not to Xu Hanyang. Yet there are also interesting informations not seen in other books. The Yanpu is included in the collectanea Baichuan xuehai, Shuofu 說郛 and Siku quanshu 四庫全書.
Source: Li Xueqin 李學勤, Lü Wenyu 呂文鬰 (1996). Siku da cidian 四庫大辭典, vol. 2, p. 1853. Changchun: Jilin daxue chubanshe.