TY  - JOUR
AU  - Saadat Mehr, Ayub 
AU  -  Dastmard, Zakia
TI  - Analysis of the content of Persian books in the second half of the elementary school (sixth grade)
JO  -  Environmental sciences and geography knowledge
VL  - 1
IS  - 2
SP  - 
EP  - 
PY  - 2021
DO  - 
ER  -