J. Llibre, A. Makhlouf.
Periodic solutions for periodic second-order differential equations with variable potentials.
J. Appl. Anal., 24(2), 127-137. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, Y. P. Martinez Mancilla, C. Vidal.
Linear type centers of polynomial Hamiltonian systems with nonlinearities of degree 4 symmetric with respect to the y-axis.
Discrete Contin. Dyn. Syst. Ser. B, 23(2), 887-912. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. M. Martins, D. J. Tonon.
Limit cycles of piecewise smooth differential equations on two dimensional torus.
J. Dyn. Diff. Equat., 30, 1011-1027. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, M. Messias, A. C. Reinol.
Quadratic three-dimensional differential systems having invariant planes with total multiplicity nine.
Rend. Circ. Mat. Palermo (2), 67, 569-580. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, A. Murza.
Darboux theory of integrability for real polynomial vector fields on $\mathbb S^n$.
Dyn. Syst., 1-14. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, D. E. Nuñez, A. Rivera.
Periodic solutions of the Nathanson's and the comb-drive finger models.
Internat. J. Non-Linear Mech., 104, 109-115. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. D. S. Oliveira.
Quadratic systems with an invariant conic having darboux invariants.
Commun. Contemp. Math., 20(4), 1750033 (15 pages). 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. D. S. Oliveira, C. A. B. Rodrigues.
On the periodic solutions of the Milchelson continuous and discontinuous piecewise linear differential system.
Comput. Appl. Math., 37(2), 1550-1561. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. D. S. Oliveira, C. Valls.
Phase portraits for some symmetric cubic Riccati polynomial differential equations.
Topology Appl., 234, 220-237. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. O. Ramírez, V. Ramírez.
Center problem for generalized $\lambda$-$\Omega$ differential systems.
Electron. J. Differential Equations, 2018(184), 1-23. 2018.
PreprintAbstractPreprint at DDDUAB

J. Llibre, R. O. Ramírez, V. Ramírez, N. Sadovskaia.
Centers and uniform isochronous centers of planar polynomial differential systems.
J. Dyn. Diff. Equat., . 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, M. F. d. Silva.
Phase portraits of integrable quadratic systems with an invariant parabola and an invariant straight line.
C. R. Acad. Sci. Paris Ser. I Math., . 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, V. F. Sirvent.
On Lefschetz periodic point free self-maps.
J. Fixed Point Theory Appl., 30(38), 9 pages. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, M. A. Teixeira.
Periodic orbits of continuous and discontinuous piecewise linear differential systems via first integrals.
Sao Paulo J. Math. Sci., 12, 121-135. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, M. A. Teixeira.
Piecewise linear differential systems with only centers can create limit cycles?
Nonlinear Dynam., 91, 249-255. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, Y. Tian.
Algebraic limit cycles bifurcating from algebraic ovals of quadratic centers.
Internat. J. Bifur. Chaos Appl. Sci. Engrg., 28(12), 1-7. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, D. J. Tonon.
The symmetric periodic orbits for the classical helium atom.
Lett. Math. Phys., 108, 1851-1871. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, C. Valls.
On the Darboux integrability of the Hindmarsh-Rose burster.
Acta Math. Sin. (Engl. Ser.), 34(6), 947-958. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, C. Valls.
Algebraic limit cycles for quadratic polynomial differential systems.
Discrete Contin. Dyn. Syst. Ser. B, 23(6), 2475-2485. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB

J. Llibre, C. Valls.
Global phase portraits of quadratic systems with a complex ellipse as invariant algebraic curve.
Acta Math. Sinica (N.S.), 34(5), 801-811. 2018. [DOI]
PreprintAbstractPreprint at DDDUAB