The relation between the \Sl(∞) algebra of flows commuting with the KP hierarchy and the Kac-Moody-Virasoro Lie point symmetries of individual equations is established. This is used to calculate the point symmetries for all equations in the hierarchy.
@article{arxiv.hep-th/9403005,
title = {Symmetries of the Kadomstev-Petviashvili Hierarchy},
author = {A. Yu. Orlov and P. Winternitz},
journal= {arXiv preprint arXiv:hep-th/9403005},
year = {2007}
}