Cosmic Ray Air Shower Characteristics in the Framework of the   Parton-Based Gribov-Regge Model NEXUS
  The purpose of this paper is twofold: first we want to introduce a new type of hadronic interaction model (NEXUS), which has a much more solid theoretical basis as, for example, presently used models like QGSJET and VENUS, and ensures therefore a much more reliable extrapolation towards high energies. Secondly, we want to promote an extensive air shower (EAS) calculation scheme, based on cascade equations rather than explicit Monte Carlo simulations, which is very accurate in calculations of main EAS characteristics and extremely fast concerning computing time. We employ the NEXUS model to provide the necessary data on particle production in hadron-air collisions and present the average EAS characteristics for energies 10^14 - 10^17 eV. The experimental data of the casa-blanka group are analyzed in the framework of the new model. 
G. Bossard, H.J. Drescher, N.N. Kalmykov, S. Ostapchenko, A.I. Pavlov,   T. Pierog, E.A. Vishnevskaya, K. Werner