Kalnins E.G. Superintegrability in two-dimensional euclidean space and associated polynomial solutions / E. G. Kalnins, W. Miller, G. S. Pogosyan, 1996. - 27 p. - Текст : непосредственный.
Superintegrability on the two dimensional hyperboloid / Ye.Hakobyan,E.G.Kalnins,W.Miller,G.S.Pogosyan, 1998. - 18 p. - Текст : непосредственный.