A. A. Chaudhry, M. Z. Siddiq, N. Chaudhrt, and A. Khan, “Indications of Penetrating Keratoplasty at Madina Teaching Hospital Faisalabad over a Period of 12 Years (1998 – 2010)”, Annals KEMU, vol. 17, no. 1, p. 61, Sep. 2011.