@article{CRMATH_2015__353_10_931_0,
     author = {Ben-Artzi, Jonathan and Hansen, Anders C. and Nevanlinna, Olavi and Seidel, Markus},
     title = {New barriers in complexity theory: {On} the solvability complexity index and the towers of algorithms},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {931--936},
     publisher = {Elsevier},
     volume = {353},
     number = {10},
     year = {2015},
     doi = {10.1016/j.crma.2015.08.002},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/j.crma.2015.08.002/}
}