Strong decays of P wave baryons in the $1/N_c$ expansion
  The hadronic decays of non-strange negative parity baryons are analyzed in the framework of the 1/Nc expansion. A complete basis of spin-flavor operators for the pseudoscalar meson S and D partial wave amplitudes is established to order 1/Nc and the unknown effective coefficients are determined by fitting to the empirically known widths. A set of relations between widths that result at the leading order, i.e. order Nc^0, is given and tested with the available data. 
N.N. Scoccola