== Resurse utile ==

* REDUCTION OF ROUND-OFF ERROR IN SYMPLECTIC INTEGRATORS

https://ncit-cluster.grid.pub.ro/trac/PP2009/wiki/Symplectic?action=edit

* Symplectic Integration without Roundoff Error

http://arxiv.org/abs/astro-ph/9408024

* Symplectic Integrators: Rotations and Roundoff Errors

http://www.springerlink.com/content/kn6m2034852485q3/

* A Class of Symplectic Integrators with Adaptive Time Step for Separable Hamiltonian Systems

http://www.iop.org/EJ/abstract/1538-3881/118/5/2532