1. Invited talk in the Proceedings of the 1971 International Symposium on Electron and Photon Interactions at High Energies;Kendall,1971
2. P. Gnädig, Eötvös University Thesis; P. Gnädig and J. Kuti, to be published.
3. The hydrogen hyperfine structure and inelastic electron proton scattering experiments
4. E. Gajzágó, private communication.
5. Invited talk given at the Amsterdam International Conference on Elementary Particles;Lee,1971