Figure 1. The bi-quintic B-spline B33 centered on (3,3) covering 36 finite elements of side 1

From

The Modified Bi-quintic B-spline Base Functions: An Application to Diffusion Equation

S. Kutluay, N. M. Yagmurlu

International Journal of Partial Differential Equations and Applications. 2017, 5(1), 26-32 doi:10.12691/ijpdea-5-1-4