Howchung Lee, Hiuling Ng 李孝聪，吴晓灵. OEC Level 4 Student's Book 4: The directions 方向

Oxford University Press 牛津大学出版社, 2020. — 24 p. — ISBN 9780190470104.Oxford Elementary Chinese (OEC) is a four-level series, designed for young learners of Chinese. The series enables learners to build strong listening and speaking skills using a communicative approach based on engaging stories and activities. It also helps them develop an interest in reading, writing, and different cultures.