TY  - BOOK
AU  - Yicheng, Z.
AU  - Huzhang, Liu com./
AU  - Guanping, Cai com./
AU  - Yicheng, Liu
TI  - Education and science
U1  - 379.51 
PY  - 1983///
CY  - Beijing
PB  - Foreign Lang. Press
KW  - Education
ER  -