Lǐ Chúnfēng 李淳風 (602–670) was an early-Táng polymath — court astronomer, mathematician, and calendar-reformer — author of the Lín dé lì 麟德曆 calendar (665), commentator on the Shí bù suàn jīng 十部算經 (Ten Mathematical Classics), and co-author with Yuán Tiāngāng 袁天綱 of the famous prophetic Tuī bèi tú 推背圖. Also credited pseudepigraphically as author of Daoist ritual-divinatory texts, including KR5d0035 Jīn suǒ liú zhū yǐn 金鎖流珠引 (29 juàn) — a massive ritual-astrological compendium.