How prove angular momentum is conserved from the Lagrangian.

Hey,

It's a simple question (hope so). How do you know (analitically) wether angular momentum is conserved based solely on the Lagrangian? Let me elaborate, for example to prove that the linear momentum is conserved you simply look for cyclic coordinates, i.e
[tex]\frac{\partial L}{\partial q_i}=0[/tex]
Or if the lagrangian isn't time dependent energy is conserved, i.e
[tex]\frac{\partial L}{\partial t}=0[/tex]
Is there a neat way as above to use in order to prove angular momentum is conserved?

Thanks,

M.