Although attributed to Garga, it was definitely not composed by the ancient astrologer of that name, and can be dated to 6th-7th century CE.
[1] Based on its mathematical contents, Michio Yano dates Garga-samhita to 6th-7th century CE.
[2] The text is known from a manuscript kept at the Vishveshvaranand Vedic Research Institute (VVRI), Hoshiarpur.
[3] The VVRI manuscript 2069 was copied by Thakura Datta Joshi and collated by Hariprasada Sharma at Hoshiarpur in 1960.
[5] Written in the style of the Puranas, the text features a dialogue between the sages Bharadvaja and Garga.