Beijing Ancient Observatory.

MLA

肖军 - Xiao Jun, and 李东生 - Li Dongsheng. Beijing Ancient Observatory. S.l.: s.n., n.d.

APA

肖军 - Xiao Jun, 肖. - Xiao Jun, & 李东生 - Li Dongsheng, 李. - Li Dongsheng. (n.d). Beijing Ancient Observatory. S.l.: s.n.

Chicago

肖军 - Xiao Jun, and 李东生 - Li Dongsheng. Beijing Ancient Observatory. S.l.: s.n., n.d.