The following reference works is cited in this example problem:
Nie, J., Degrassi, G., Hofmayer, C. & Ali, S. (2008). Nonlinear Seismic
                    Correlation Analysis of the JNES/NUPEC Large-Scale Piping System Tests.
                        ASME Pressure Vessels and Piping Division Conference. PVP2008
                        Proceedings.