Shanghai geming jiaoyu chubanshe (上海革命教育出版社)
From (incomplete) series on the martyr Men He, in the center of this image, raising his right arm.
The text on the red flag:
人民公社好 - The People's Commune is good
中国人民解放軍駐青海省部队 - Chinese People's Liberation Army Troops in Qinghai Province