Đăng bởi Nguyễn Bình
"nguon-goc-nen-van-minh-sumer"
"ton-giao-va-xa-hoi-cua-nguoi-sumer"
"mot-so-thanh-tuu-cua-nen-van-minh-sumer"
"kinh-te-nong-nghiep-cua-nguoi-sumer"