Using the Lax representation with non-removable parameter, we construct two hierarchies of nonlocal conservation laws for the 3D rdDym equation uty=uxuxy−uyuxx and describe the algebras of nonlocal symmetries in the corresponding coverings.
@article{arxiv.1507.00897,
title = {Coverings over Lax integrable equations and their nonlocal symmetries},
author = {H. Baran and I. S. Krasil'shchik and O. I. Morozov and P. Vojcak},
journal= {arXiv preprint arXiv:1507.00897},
year = {2016}
}