@article{AIF_1984__34_1_207_0, author = {Boman, Jan}, title = {On the closure of spaces of sums of ridge functions and the range of the $X$-ray transform}, journal = {Annales de l'Institut Fourier}, pages = {207--239}, publisher = {Imprimerie Louis-Jean}, address = {Gap}, volume = {34}, number = {1}, year = {1984}, doi = {10.5802/aif.957}, zbl = {0521.46018}, mrnumber = {85j:44002}, language = {en}, url = {https://aif.centre-mersenne.org/articles/10.5802/aif.957/} }