Sattar, A. et al. 2009. CHANGING TRENDS IN FREQUENCY OF EXTENDED SPECTRUM BETA LACTAMASE PRODUCING GRAM NEGATIVE BACILLI IN INTENSIVE CARE UNITS OF A TERTIARY CARE HOSPITAL: Changing trends in Frequency of Expended Spectrum Beta Lactamase. Pakistan Armed Forces Medical Journal. 59, 3 (Sep. 2009), 271–74.