Experimental Investigation of the Nature of the Knee in the Primary   Cosmic Ray Energy Spectrum with the GAMMA experiment
  We present preliminary results obtained by a novel difference method for the study of the nature of the knee in the energy spectrum of the primary cosmic radiation. We have applied this method to data from the GAMMA experiment in Armenia. The analysis provides evidence for the possible existence of a nearby source of primary cosmic rays in the Southern hemisphere. 
V.P.Pavlyuchenko, R.M.Martirosov, N.M.Nikolskaya, A.D.Erlykin,   H.A.Babayan, A.P.Garyaka, H.S.Vardanyan, L.W.Jones, J.Kempa...
astro-ph.HE