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  1. Restricted Quaternion Two-Sided Matrix Equations with Weighted Drazin-Star and Star-Drazin Solutions

    Article • Advances in Applied Clifford Algebras, January 2026, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  2. The determinant of the adjacency matrix of a quaternion unit gain graph

    Article • Discrete Mathematics, January 2026, Elsevier

    Dr. Ivan I. Kyrchei

  3. Quaternion Generalized Inverses

    Article • January 2026, Elsevier

    Dr. Ivan I. Kyrchei

  4. Analysis of Solvability and Representation of General Solutions for Anti-Hermitian Constrained Quaternion Matrix Equations

    Article • April 2025, MDPI AG

    Dr. Ivan I. Kyrchei

  5. The Right–Left WG Inverse Solutions to Quaternion Matrix Equations

    Article • Symmetry, December 2024, MDPI AG

    Dr. Ivan I. Kyrchei

  6. The Right-Left Wg Inverse Solutions to Quaternion Matrix Equations

    Article • November 2024, MDPI AG

    Dr. Ivan I. Kyrchei

  7. Hermitian solution to constraint system of generalized Sylvester quaternion matrix equations

    Article • Arabian Journal of Mathematics, October 2024, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  8. Quaternion Differential Matrix Equations with Singular Coefficient Matrices

    Article • Qualitative Theory of Dynamical Systems, June 2024, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  9. The determinant of the Laplacian matrix of a quaternion unit gain graph

    Article • Discrete Mathematics, June 2024, Elsevier

    Dr. Ivan I. Kyrchei

  10. Index-MP and MP-index matrices

    Article • Journal of Mathematical Analysis and Applications, May 2024, Elsevier

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  11. Solvability and algorithm for Sylvester-type quaternion matrix equations with potential applications

    Article • AIMS Mathematics, January 2024, Tsinghua University Press

    Victor Leiva, Dr. Ivan I. Kyrchei

  12. W-MPCEP–N-CEPMP-solutions to quaternion matrix equations with constrains

    Article • Revista de la Real Academia de Ciencias Exactas Físicas y Naturales Serie A Matemáticas, August 2023, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  13. Compact formula for skew-symmetric system of matrix equations

    Article • Arabian Journal of Mathematics, August 2023, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  14. Introductory Chapter: Some Preliminary Aspects of Inverse Problem

    Article • March 2023, IntechOpen

    Dr. Ivan I. Kyrchei

  15. Solving and Algorithm for Least-Norm General Solution to Constrained Sylvester Matrix Equation

    Article • March 2023, IntechOpen

    Dr. Ivan I. Kyrchei

  16. Quaternion MPCEP, CEPMP, and MPCEPMP Generalized Inverses

    Article • January 2023, IntechOpen

    Dr. Ivan I. Kyrchei

  17. W-MPD–N-DMP-solutions of constrained quaternion matrix equations

    Article • Special Matrices, January 2023, De Gruyter

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  18. Quaternion Two-Sided Matrix Equations with Specific Constraints

    Article • January 2023, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  19. Solving and Algorithm to System of Quaternion Sylvester-Type Matrix Equations with $$*$$-Hermicity

    Article • Advances in Applied Clifford Algebras, August 2022, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  20. Closed-form formula for a classical system of matrix equations

    Article • Arab Journal of Basic and Applied Sciences, August 2022, Taylor & Francis

    Dr. Ivan I. Kyrchei

  21. Representations of Quaternion W-MPCEP, W-CEPMP and W-MPCEPMP Inverses

    Article • Advances in Applied Clifford Algebras, May 2022, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  22. MPCEP-$$*$$CEPMP-Solutions of Some Restricted Quaternion Matrix Equations

    Article • Advances in Applied Clifford Algebras, February 2022, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  23. Generalized Inverses: Algorithms and Applications

    Article • January 2022, Nova Science Publishers, Inc.

    Dr. Ivan I. Kyrchei

  24. Sign pattern, usability, representations and perturbation for the core-EP and weighted core-EP inverse

    Article • Applied Mathematics and Computation, September 2021, Elsevier

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  25. MPD-DMP-solutions to quaternion two-sided restricted matrix equations

    Article • Computational and Applied Mathematics, June 2021, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  26. Weighted Minimization Problems for Quaternion Matrices

    Article • Advances in Applied Clifford Algebras, June 2021, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  27. Constraint Solution of a Classical System of Quaternion Matrix Equations and Its Cramer’s Rule

    Article • Iranian Journal of Science and Technology Transactions A Science, March 2021, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  28. Representations and properties for the MPCEP inverse

    Article • Journal of Applied Mathematics and Computing, January 2021, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  29. Solvability of New Constrained Quaternion Matrix Approximation Problems Based on Core-EP Inverses

    Article • Advances in Applied Clifford Algebras, November 2020, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Ph.D. Predrag S. Stanimirovic

  30. Weighted quaternion core-EP, DMP, MPD, and CMP inverses and their determinantal representations

    Article • Revista de la Real Academia de Ciencias Exactas Físicas y Naturales Serie A Matemáticas, September 2020, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  31. Determinantal Representations of the Weighted Core-EP, DMP, MPD, and CMP Inverses

    Article • Journal of Mathematics, May 2020, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  32. Determinantal Representations for the Solution of the Generalized Sylvester Quaternion Matrix Equation

    Article • Journal of Mathematical Sciences, February 2020, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  33. Explicit formulas and determinantal representation for η-skew-Hermitian solution to a system of quaternion matrix equations

    Article • Filomat, January 2020, National Library of Serbia

    Dr. Ivan I. Kyrchei

  34. Determinantal Representations of the Quaternion Core Inverse and Its Generalizations

    Article • Advances in Applied Clifford Algebras, October 2019, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  35. Determinantal Representations of the Core Inverse and Its Generalizations with Applications

    Article • Journal of Mathematics, October 2019, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  36. Least-Norm of the General Solution to Some System of Quaternion Matrix Equations and Its Determinantal Representations

    Article • Abstract and Applied Analysis, August 2019, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei, abdur rehman

  37. The General Solution of Quaternion Matrix Equation Having η-Skew-Hermicity and Its Cramer’s Rule

    Article • Mathematical Problems in Engineering, July 2019, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  38. Cramer’s Rules of $$\pmb {\eta }$$ η ...

    Article • Advances in Applied Clifford Algebras, June 2019, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  39. Determinantal representations of solutions to systems of two-sided quaternion matrix equations

    Article • Linear and Multilinear Algebra, May 2019, Taylor & Francis

    Dr. Ivan I. Kyrchei

  40. Determinantal Representations of General and (Skew-)Hermitian Solutions to the Generalized Sylvester-Type Quaternion Matrix Equation

    Article • Abstract and Applied Analysis, January 2019, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  41. Cramer’s rules for the system of quaternion matrix equations with η-Hermicity

    Article • 4open, January 2019, EDP Sciences

    Dr. Ivan I. Kyrchei

  42. Determinantal Representations of Solutions and Hermitian Solutions to Some System of Two-Sided Quaternion Matrix Equations

    Article • Journal of Mathematics, November 2018, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  43. Cramer’s Rules for Sylvester Quaternion Matrix Equation and Its Special Cases

    Article • Advances in Applied Clifford Algebras, September 2018, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  44. Cramer’s Rules for the System of Two-Sided Matrix Equations and of Its Special Cases

    Article • August 2018, IntechOpen

    Dr. Ivan I. Kyrchei

  45. Determinantal Representations of Solutions to Systems of Quaternion Matrix Equations

    Article • Advances in Applied Clifford Algebras, February 2018, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  46. Explicit determinantal representation formulas for the solution of the two-sided restricted quaternionic matrix equation

    Article • Journal of Applied Mathematics and Computing, November 2017, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  47. Weighted singular value decomposition and determinantal representations of the quaternion weighted Moore–Penrose inverse

    Article • Applied Mathematics and Computation, September 2017, Elsevier

    Dr. Ivan I. Kyrchei

  48. Cramer’s Rules for Some Hermitian Coquaternionic Matrix Equations

    Article • Advances in Applied Clifford Algebras, January 2017, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  49. Explicit Determinantal Representation Formulas ofW-Weighted Drazin Inverse Solutions of Some Matrix Equations over the Quaternion Skew Field

    Article • Mathematical Problems in Engineering, January 2016, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  50. Applications of Methods of Numerical Linear Algebra in Engineering 2016

    Article • Mathematical Problems in Engineering, January 2016, Hindawi Publishing Corporation

    Dr. Ivan I. Kyrchei

  51. Determinantal representations of the W-weighted Drazin inverse over the quaternion skew field

    Article • Applied Mathematics and Computation, August 2015, Elsevier

    Dr. Ivan I. Kyrchei

  52. Preface

    Article • Vietnam Journal of Mathematics, May 2015, Springer Science + Business Media

    Dr. Ivan I. Kyrchei, Noel Carroll, Aldo Franco Dragoni

  53. The Column and Row Immanants Over A Split Quaternion Algebra

    Article • Advances in Applied Clifford Algebras, January 2015, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  54. Preface of the “Minisymposium on theory and application of matrix equations”

    Article • January 2015, American Institute of Physics

    Dr. Ivan I. Kyrchei

  55. Determinantal representations of the Drazin inverse over the quaternion skew field with applications to some matrix equations

    Article • Applied Mathematics and Computation, July 2014, Elsevier

    Dr. Ivan I. Kyrchei

  56. Explicit formulas for determinantal representations of the Drazin inverse solutions of some matrix and differential matrix equations

    Article • Applied Mathematics and Computation, March 2013, Elsevier

    Dr. Ivan I. Kyrchei

  57. Explicit representation formulas for the minimum norm least squares solutions of some quaternion matrix equations

    Article • Linear Algebra and its Applications, January 2013, Elsevier

    Dr. Ivan I. Kyrchei

  58. Preface of the "Mini symposium on generalized inverses and their applications"

    Article • January 2013, American Institute of Physics

    Dr. Ivan I. Kyrchei

  59. Analogs of Cramer’s rule for the minimum norm least squares solutions of some matrix equations

    Article • Applied Mathematics and Computation, February 2012, Elsevier

    Dr. Ivan I. Kyrchei

  60. Determinantal representation of the Moore–Penrose inverse matrix over the quaternion skew field

    Article • Journal of Mathematical Sciences, December 2011, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  61. Determinantal representations of the Moore–Penrose inverse over the quaternion skew field and corresponding Cramer's rules

    Article • Linear and Multilinear Algebra, April 2011, Taylor & Francis

    Dr. Ivan I. Kyrchei

  62. Cramer’s rule for some quaternion matrix equations

    Article • Applied Mathematics and Computation, November 2010, Elsevier

    Dr. Ivan I. Kyrchei

  63. Cramer's rule for quaternionic systems of linear equations

    Article • Journal of Mathematical Sciences, November 2008, Springer Science + Business Media

    Dr. Ivan I. Kyrchei

  64. Analogs of the adjoint matrix for generalized inverses and corresponding Cramer rules

    Article • Linear and Multilinear Algebra, July 2008, Taylor & Francis

    Dr. Ivan I. Kyrchei

  65. Fractional-rational regularization of a system of linear equations over the skew-field of quaternions

    Article • Journal of Mathematical Sciences, July 1998, Springer Science + Business Media

    Dr. Ivan I. Kyrchei