Local Lipschitz property for the Chebyshev center mapping over N-nets Pyotr N. Ivanshin; Evgenii N. Sosov — 2008 Matematički Vesnik
Algebras of functions on groupoid of some special foliations. Ivanshin, Pyotr N. — 2003 Southwest Journal of Pure and Applied Mathematics [electronic only]
Structure of function algebras on foliated manifolds. Ivanshin, Pyotr N. — 2004 Lobachevskii Journal of Mathematics