Long-range interactions in α-helical proteins with interspine coupling: Modulational instability and exact soliton solutionsAlain Mvogo, Germain Hubert Ben-Bolie and Timoléon Crépin KofanéEur. Phys. J. B, 86 10 (2013) 413DOI: https://doi.org/10.1140/epjb/e2013-40517-1