Early-Táng literatus, compiler — by command of Lǐ Yùn 李惲, Prince Jiāng 蔣王 (d. 674), the seventh son of Tàizōng — of the Tùyuán cèfǔ 兔園策府 (KR3k0069), a thirty-juàn, forty-eight-chapter parallel-prose examination primer that was the most influential village-school cūnshū of the late Táng and Five Dynasties. CBDB id 92858 records him under “fl. 638”; Ulrich Theobald’s ChinaKnowledge.de article, drawing on Chinese scholarship on the Dūnhuáng witnesses, proposes lifedates of 634–712 but these are not securely attested in standard sources and remain conjectural. The biographical record is thin: he served on the staff of Prince Jiāng and was responsible for producing the Tùyuán cèfǔ as a teaching manual for the prince’s clients and clients’ sons; nothing else by him survives. Because Lǐ Yùn died in 674, the Tùyuán cèfǔ must have been completed before that year. There is no Dù Sìxiān biography in Jiù Tángshū or Xīn Tángshū; his name surfaces only in the Xīn Tángshū “Yìwénzhì” listing for the Tùyuán cèfǔ and in the (now lost) preface fragments recovered from Dūnhuáng. CBDB also lists a second person of the same name (id 379038) without dates; the present note follows id 92858 as the conventional referent of the Tùyuán cèfǔ attribution.