Asymptotic behavior of global entropy solutions for nonstrictly   hyperbolic systems with linear damping
  In this paper we investigate the large time behavior of the global weak entropy solutions to the symmetric Keyftiz-Kranzer system with linear damping. It is proved that as t tends to infinite the entropy solutions tend to zero in the L p norm 
Juan C. Juajibioy, Richard A De la Cruz, Leonardo Rendon
math.AP