Rostislav Grigorchuk (IMAGE) American Mathematical Society Caption Rostislav Grigorchuk is the winner of the 2015 American Mathematical Society Leroy P. Steele Prize for Seminal Contribution to Research. Credit None Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.