Determination of the a0-a2 pion scattering length from K->pi+ pi0 pi0   decay
  We present a new method for the determination of the pion-pion scattering lenght combination a0-a2, based on the study of the pi0-pi0 spectrum in K->pi+ pi0 pi0 in the vicinity of the pi+ pi- threshold. The method requires a minimum of theoretical input, and is potentially very accurate. 
Nicola Cabibbo