N. Kruff, J. Llibre, C. Pantazi, S. Walcher.
Invariant algebraic surfaces of polynomial vector fields in dimension three.
J. Dyn. Diff. Equat., . 2021. [DOI]
AbstractFull PDFOA at DDDUAB

S. Li, C. Liu, J. Llibre.
The planar discontinuous piecewise linear refracting systems have at most one limit cycle.
Nonlinear Anal. Hybrid Syst., 41, 101045:1-14. 2021. [DOI]
PreprintAbstractOA at DDDUAB

T. Li, J. Llibre.
Limit cycles in piecewise polynomial systems allowing a non-regular switching boundary.
Phys. D, 419, 132855:1-13. 2021. [DOI]
PreprintAbstractOA at DDDUAB

T. Li, J. Llibre.
Limit cycles of piecewise polynomial differential systems with the discontinuity line xy=0.
Commun. Pure Appl. Anal., 20(11), 3871-3893. 2021. [DOI]
PreprintAbstractOA at DDDUAB

T. Li, J. Llibre.
Phase portraits of separable quadratic systems and a bibliographical survey on quadratic systems.
Exposition. Math., 39, 540-565. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre.
Central configurations of the circular restricted 4-body problem with three equal primaries in the collinear central configuration of the 3-body problem.
Trends in Computer Science and Information Technology, 6(1), 1-6. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre.
Integrability and limit cycles via first integrals.
Symmetry (Basel), 13(9), 1-21. 2021. [DOI]
AbstractFull PDFOA at DDDUAB

J. Llibre, J. R. Moraes.
Limit cycles of 3-dimensional discontinuous piecewise differential systems formed by linear centers.
Sao Paulo J. Math. Sci., 15(2), 858-874. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, B. D. Lopes, P. R. Silva.
Bifurcations of the Riccati quadratic polynomial differential system.
Internat. J. Bifur. Chaos Appl. Sci. Engrg., 31(6), 2150094:1-13. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, L. d. A. S. Menezes.
The Markus–Yamabe conjecture does not hold for piecewise discontinuous linear differential systems separated by one straight line.
J. Dyn. Diff. Equat., 33, 659-676. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, M. Messias, A. C. Reinol.
Global dynamics and bifurcation of periodic orbits in a modified Nosé-Hoover oscillator.
J. Dyn. Control Syst., 27, 491-506. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, A. Murza.
Polynomial vector fields on the Clifford torus.
Internat. J. Bifur. Chaos Appl. Sci. Engrg., 31(4), 2150057:1-5. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, R. D. S. Oliveira, C. A. B. Rodrigues.
Quadratic systems with an invariant algebraic curve of degree 3 and a Darboux invariant.
Electron. J. Differential Equations, 2021(69), 1-52. 2021.
PreprintAbstractOA at DDDUAB

J. Llibre, R. D. S. Oliveira, Y. Zhao.
On the birth and death of algebraic limit cycles in quadratic differential systems.
European J. Appl. Math., 32, 317-336. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, D. Pasca, C. Valls.
The circular restricted 4-body problem with three equal primaries in the collinear central configuration of the 3-body problem.
Celestial Mech. Dynam. Astronom., 133(53), 1-13. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, C. Pessoa, J. D. Ribeiro.
Rational first integrals of the Liénard equations: The solution to the Poincaré problem for the Liénard equations.
An. Acad. Brasil. Ci., 93(4), 1-7. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, R. O. Ramírez, V. Ramírez.
Complete integrability of vector fields in $R^N$.
J. Geom. Phys., 168, 104308:1-25. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, R. O. Ramírez, V. Ramírez.
The center problem for the class of $\lambda$-$\Omega$ differential systems.
Rend. Circ. Mat. Palermo (2), 70, 1483-1499. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, A. Sá.
Minimal set of periods for continuous self-maps of the eight space.
Fixed Point Theory Algorithms Sci. Eng., 2021(3), 1-26. 2021. [DOI]
PreprintAbstractOA at DDDUAB

J. Llibre, T. Saeed, E. E. Zotos.
Periodic orbits and equilibria for a seventh-order generalized Hénon-Heiles Hamiltonian system.
J. Geom. Phys., 167, 104290:1-12. 2021. [DOI]
PreprintAbstractOA at DDDUAB