Excitation of nitrogen molecular ions in a strong laser field by electron recollisions Vladimir T. Tikhonchuk, Jean-Félix Tremblay-Bugeaud, Yi Liu, Aurélien Houard and André Mysyrowicz Eur. Phys. J. D, 71 11 (2017) 292 Published online: 16 November 2017 DOI: 10.1140/epjd/e2017-80464-3