The Shen Nong shu 神農書 "Book of the Divine Husbandman" was a treatise on agriculture written by an unknown author at an unknown point of time. The "Divine Husbandman" Shen Nong 神農 is a mythical person to whom the invention of agriculture and herbal medicine are attributed. The book was twenty chapters long but went lost at an early point of thime. The Qing period 清 (1644-1911) scholar Ma Guohan 馬國翰 has collected fragements of it quoted in the books Guanzi 管子, Lüshi chunqiu 呂氏春秋, Huainanzi 淮南子, Liuzi xinlun 劉子新論, and, most important, the Tang period 唐 (618-907) book Kaiyuan zhanjing 開元占經. These are to be found in Ma Guohan's reprint series Yuhanshanfang jiyi shu 玉函山房輯佚書.
Source: Li Xueqin 李學勤, Lü Wenyu 呂文鬰 (1996). Siku da cidian 四庫大辭典, vol. 2, p. 1644. Changchun: Jilin daxue chubanshe.