Symmetry analysis of evolution type equations VI Lahno, SV Spichak, VI Stogniy Computer Research Institute, Moscow–Igevsk, 2004 | 81* | 2004 |

Symmetry classification and exact solutions of the one-dimensional Fokker-Planck equation with arbitrary coefficients of drift and diffusion S Spichak, V Stognii Journal of Physics A: Mathematical and General 32 (47), 8341, 1999 | 57 | 1999 |

Ñèìåòð³éíèé àíàë³ç ð³âíÿíü åâîëþö³éíîãî òèïó Â² Ëàãíî, ÑÂ Ñï³÷àê, Â² Ñòîãí³é Ïðàö³ Ií–òó ìàòåìàòèêè ÍÀÍ Óêðà¿íè: Ìàòåìàòèêà òà ¿¿ çàñòîñóâàííÿ.—K 45, 359, 2002 | 52 | 2002 |

Symmetries and modelling functions for diffusion processes AG Nikitin, SV Spichak, YS Vedula, AG Naumovets Journal of Physics D: Applied Physics 42 (5), 055301, 2009 | 45 | 2009 |

ÑÈÌÅÒÐ²ÉÍÈÉ ÀÍÀË²Ç ² ÒÎ×Í² ÐÎÇÂ’ßÇÊÈ Ë²Í²ÉÍÎÃÎ Ð²ÂÍßÍÍß ÊÎËÌÎÃÎÐÎÂÀ ÑÂ Ñï³÷àê, Â² Ñòîãí³é, ²Ì Êîïàñü | 17* | 2011 |

On the connection between solutions of Dirac and Maxwell equations, dual Poincaré invariance and superalgebras of invariance and solutions of nonlinear Dirac equations WI Fushchich, WM Shtelen, SV Spichak Journal of Physics A: Mathematical and General 24 (8), 1683, 1991 | 14 | 1991 |

Symmetry classification and exact solutions of the Kramers equation S Spichak, V Stognii Journal of Mathematical Physics 39 (6), 3505-3510, 1998 | 11 | 1998 |

On algebraic classification of Hermitian quasi-exactly solvable matrix Schrödinger operators on line S Spichak, R Zhdanov Journal of Physics A: Mathematical and General 32 (20), 3815, 1999 | 10 | 1999 |

Symmetry analysis of the Kramers equation S Spichak, V Stogny Reports on Mathematical Physics 40 (1), 125-130, 1997 | 10 | 1997 |

One-dimensional Fokker–Planck equation invariant under four-and six-parametrical group S Spichak, V STOGNII Proc. of the Third Int. Conf.“Symmetry in nonlinear mathematical physics …, 2000 | 8 | 2000 |

Group classification of quasilinear elliptic-type equations. I. Invariance with respect to Lie algebras with nontrivial Levi decomposition VI Lahno, SV Spichak Ukrainian Mathematical Journal 59 (11), 1719-1736, 2007 | 7 | 2007 |

Symmetry analysis of equations of evolution type VI Lahno, SV Spichak, VI Stohnii Institute of Computer Investigations, Moscow, 2004 | 5 | 2004 |

Symmetry analysis of the evolution equations VI Lagno, SV Spichak, VI Stogniy Moscow-Izhevsck: Institute of Computer Investigations, 2004 | 5 | 2004 |

Simmetriynyy analiz uravneniy evolyutsionnogo tipa [Symmetry analysis of evolution type equations] VI Lagno, SV Spichak, VI Stognii Moskva—Izhevsk, Institute of Computer Sciences, 2004 | 5 | 2004 |

Group classification of a class of generalized nonlinear Kolmogorov equations and exact solutions I Rassokha, M Serov, S Spichak, V Stogniy Journal of Mathematical Physics 59 (7), 2018 | 4 | 2018 |

Preliminary classification of realizations of two-dimensional Lie algebras of vector fields on a circle SV Spichak Sixth Workshop Group Analysis of Differential Equations and Integrable …, 2013 | 4 | 2013 |

Symmetric classification of the one-dimensional Fokker–Planck–Kolmogorov equation with arbitrary drift and diffusion coefficients SV Spichak, VI Stognii Neliniıni Kolyv 2, 401-413, 1999 | 4 | 1999 |

Conditional symmetry and exact solutions of the Kramers equation S Spichak, V Stognii Symmetry in Nonlinear Mathematical Physics 1, 2, 1997 | 4 | 1997 |

Group classification of quasilinear elliptic-type equations. II. Invariance under solvable Lie algebras VI Lahno, SV Spichak Ukrainian Mathematical Journal 63 (2), 236-254, 2011 | 3 | 2011 |

Invariance of Maxwell’s Equations under Nonlinear Representations of Poincaré Algebra S SPICHAK Proceedings of Institute of Mathematics of NAS of Ukraine 50 (Part 2), 961-964, 2004 | 2 | 2004 |