“…In mechanics, physics, and many engineering applications, the biharmonic equation is used as a governing equation to describe: the deformation of thin plates, the motion of fluids, free boundary problems, non-linear elasticity, and problems related to blending surfaces. Several implementations of the 2D biharmonic problem have been consecrated in simply and multiply-connected regions (see, e.g., [3,5,1,8,9,21,13,19,22,4,10,12]). Boundary conditions are essential and extremely important constraints for solving a boundary value problem.…”