佛祖統紀 35.14

35.14

元壽元年。遣景憲使大月氏。得其王口授浮圖經還。當時稍有行齎戒者（魏書佛老志。浮圖亦佛陀。此云覺者）。

In the first year of the Yuanshou era, Jing Xian was sent as an envoy to the Da Yuezhi, and returned having received an oral transmission of the Futu jing (Buddhist sūtra) from their king. At that time, there were already a few who received and observed precepts (The "Treatise on Buddhism and Daoism" in the Book of Wei states: "'Futu' is also 'Fotuo'; here translated as 'the Awakened One'").