TT - UT in the seventh century derived from astronomical records
in the Nihongi, the Suishu, and the Jiu- and Xin-Tangshu
日本書紀、隋書、旧唐書および新唐書の天文史料から得た7世紀のTT - UT
Kin-aki Kawabata, Kiyotaka Tanikawa, and Mitsuru Soma
河鰭公昭、谷川清隆, 相馬 充
Astronomical Instruments and Archives from the Asia-Pacific Region
Eds. Orchiston, W., Stephenson, R., Debarbat, S., and Nha, I.S.,
Yonsei University Press, Seoul, 2003