Mathematics Achievement of Chinese, Japanese and American Children. Volume #231 - pp. 693-699, Feb. 14, 1986. The authors were Harold Stevenson, Shin-Ying Lee and James W. Stigler.
They published a follow up study in Science Magazine.
Mathematics Achievement of Chinese, Japanese and American Children: Ten Years Later Volume #259 - pp 53-58, Jan 1, 1993.The studies were separated by 10 years even though the publication dates were not.