The paper contains a brief description of Mong. E 289 unit from the collection of the Institute of Oriental Manuscripts of the Russian Academy of Sciences. This is a set of 373 folios of various formats recorded and compiled by Tatiana K. Alekseeva, a Buryat folklore scholar. Among them is the text of an epics, titled by the author as Geser qaɣan-u nom ɣaraqu-yin tuqai (“Prehistory of Geser”). The text is presented in different phonetic transcription systems. 120 folios of text in Old Mongolian scripts were done in the field. The record took place on the territory of the modern Osinsky district of the Irkutsk region during the summer of 1946 from the storyteller Morkhonoi A. Shobonov. The complex of both field record and different “whitewashed” variants of the text can help to uncover the “desktop” of the collector.