**The web of Resonances: t**he
background represents the web of resonances of the quasi-integrable
Hamiltonian:

, where are action variables, are their conjugated

angles, and is small. The set of lines in the picture represents the projection of the resonances of

the system on the plane of the actions , while the uniform background color represent the set of invariant

tori. The numerical method to obtain such a kind of
pictures is described in the paper by **Froeschle'
C., Guzzo M. and**

**Lega E. **:``Graphical
Evolution of the Arnold Web: From Order to Chaos'' published in
Science, Volume 289, n. 5487, 2000.