New non-standard Lagrangians for the Li\'enard-type equations
  Li\'enard-type equations are used for the description of various phenomena in physics and other fields of science. Here we find a new family of the Li\'enard-type equations which admits a non-standard autonomous Lagrangian. As a by-product we obtain autonomous first integrals for each member of this family of equations. We also show that some of the previously known conditions for the existence of a non-standard Lagrangian for the Li\'enard-type equations follow from the linearizability of the corresponding equation via nonlocal transformations. 
Nikolai A. Kudryashov and Dmitry I. Sinelshchikov
nlin.SI