Special issue on nonlinear phenomena in physics: new techniques and applications Anastasios Bountis, Eusebius J. Doedel, Elbert E.N. Macau, Panayotis Panayotaros and Carlos L. Pando Lambruschini Eur. Phys. J. Special Topics, 227 5-6 (2018) 457-461 Published online: 04 October 2018 DOI: 10.1140/epjst/e2018-00103-0