$\tau\to\rho\pi\pi\nu$ decays
  Effective chiral theory of mesons is applied to study the four decay modes of $\tau\to\rho\pi\pi\nu$. Theoretical values of the branching ratios are in agreement with the data. The theory predicts that the $a_{1}$ resonance plays a dominant role in these decays. There is no new parameter in this study. 
Bing An Li (Univ. of Kentucky)