Ezeagu, C. A., et al. “Destructive and Non-Destructive Assessment of Collapsed Structures in Onitsha, Anambra State, Nigeria”. American Scientific Research Journal for Engineering, Technology, and Sciences, vol. 12, no. 1, May 2015, pp. 170-86, https://www.asrjetsjournal.org/American_Scientific_Journal/article/view/564.