Classification of resonance Regge trajectories and a modified Mulholland   formula
  We employ a simple potential model to analyse the effects which a Regge trajectory, correlating with a bound or a metastable state at zero angular momentum, has on an integral cross section. A straightforward modification of the Mulholland formula of Macek et al is proposed for more efficient separation of the resonance contribution. 
D.Sokolovski, and E.Akhmatskaya
quant-ph