1. Theory workshop at DESY on HERA physics,1987
2. Study on the photon-electron storage ring project,1980
3. Experimentation at HERA, workshop organized by DESY, ECFA and NIKHEF,1983
4. Discussion meeting on HERA experiments,1984
5. Radiative corrections to neutral current deep inelastic lepton nucleon scattering at HERA energies