Alarcón Álvarez, Enrique and Cano, J.J. and Dominguez Abascal, José (1989). Boundary element approach to the dynamic stiffness functions of circular foundations. "International Journal for Numerical and Analytical Methods in Geomechanics", v. 13 (n. 6); pp. 645-664. ISSN 0363-9061. https://doi.org/10.1002/nag.1610130606.