@article{polini_2007,  title={Exclusive processes in diffraction at HERA},  volume={37},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332007000500036},  DOI={10.1590/S0103-97332007000500036},  number={2c},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Polini, A.},  year={2007},  month={Jun},  pages={813–815} }