@article {20.500.11767_81737, title = {NURBS-SEM: A hybrid spectral element method on NURBS maps for the solution of elliptic PDEs on surfaces}, journal = {COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING}, volume = {338}, year = {2018}, pages = {440{\textendash}462}, doi = {10.1016/j.cma.2018.04.039}, url = {https://arxiv.org/abs/1804.08271}, author = {Giuseppe Pitton and Luca Heltai} }