Figure 1 (IMAGE) Institute for Basic Science Caption The main theorem describes the relationship between solutions of the KdV and BKP hierarchies. The tau functions can be identified after a simple change of variables. Credit Institute for Basic Science Usage Restrictions Attribution Required License Original 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.