“…Among the common numerical techniques used are finite difference schemes, differential quadrature methods, finite volume methods, finite element methods, Haar wavelet methods, spectral methods, pseudospectral methods, method of lines, meshless methods, Adomian decomposition methods, B-spline methods, discontinuous Galerkin methods, reproducing kernel functions, etc. 10,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] However, such methods either lack the exponential convergence enjoyed by spectral and pseudospectral methods or they enjoy exponential convergence rate in the spatial direction but suffer from low-order convergence rate in the temporal direction or suffer from degradation of the observed precision because of the ill conditioning of the employed numerical differential operators to the extent that the development of efficient preconditioners becomes extremely crucial or subject to serious time step restrictions that could be more severe than those predicted by the standard stability theory. [36][37][38][39][40][41][42][43][44][45][46][47][48] To avoid the ill conditioning of differential operators and the reduction in convergence rate for derivatives, an alternative direction to the aforementioned methods is to recast the partial differential equation into its integral formulation to take advantage of the well conditioning of integral operators and then discretize the latter using various discretization techniques.…”