Integral representation of the pressure of the Stokes flow

Question

I'm currently reading these three books:

1. S. Kim, S. J. Karrila - Microhydrodynamics: Principles and Selected Applications

2. O. A. Ladyzhenskaia -The Mathematical Theory of Viscous Incompressible Flow

3. C. Pozrikidis - Introduction to Theoretical and Computational Fluid Dynamics

And I cannot work out this formula for the integral representation of the pressure,
$$ p\left(\mathbf{x}_{0}\right)=-\frac{1}{8 \pi} \iint_{D} \mathcal{P}_{i}\left(\mathbf{x}, \mathbf{x}_{0}\right) f_{i}(\mathbf{x}) \mathrm{d} S(\mathbf{x})+\frac{\mu}{4 \pi} \iint_{D} u_{i}(\mathbf{x}) \mathcal{P}_{i k}^{\Sigma}\left(\mathbf{x}, \mathbf{x}_{0}\right) n_{k}(\mathbf{x}) \mathrm{d} S(\mathbf{x}) $$

How can I find the integral representation of the pressure from the representation of the velocity?