E. Khan, T. Schneiders, A. Zafar, E. Aziz, A. Parekh, and R. Hasan, “Emergence of CTX-M Group 1-ESBL producing Klebsiella pneumonia from a tertiary care centre in Karachi, Pakistan”, J Infect Dev Ctries, vol. 4, no. 08, pp. 472–476, May 2010.