"Zhou bi suan jing." . . "周髀算經" . . . . . . . . . . . "Early works" . . . "周髀算經天文研究" . . . . . "周髀算經天文硏究" . "Zhou bi suan jing tian wen yan jiu" . . "Zhou bi suan jing." . . "周髀算經." . "Tian wen xue." . . "天文學" .