Hua bei dong bu zhong li jia su du zhi ce ding
By: Yan Yuefei, Lu Ruoyu
Contributors: Lu, Ruoyu, author
Publisher: Guo li Beiping yan jiu yuan wu li xue yan jiu suo
Published: 1933
Place of publication: Beijing
Language: chi
Number of pages: 11
Subjects: Gravity; Measurement