1. G. E. Backus, The Quarterly Journal of Mechanics and Applied Mathematics 21(2), 195 (1968).
2. J. A. Cottrell, T. J. R. Hughes, Y. Bazilevs, Isogeometric Analysis: Toward Integration of CAD and FEA (Wiley, 2009).
3. R. Haberman, Applied Partial Differential Equations with Fourier Series and Boundary Value Problems (Pearson, Southern Methodist University, 2013).
4. Dinh Nho Ho and D. Lesnic, IMA Journal of Applied Mathematics 65(2), 199 (2000).
5. J. B. Keller, SIAM Review 21(2), 229 (1979).