1. Hoffer KJ. Accuracy of ultrasound intraocular lens calculation. Arch Ophthalmol 1981; 99: 1819–23.
2. Hillmann J. S. The selection of intraocular lens power by calculation and by reference to the refraction: A clinical study. Trans Ophthalmol Soc UK 1982; 102: 495–7.
3. Panel Reports. Intraocular lens implantation: An NIH Consensus development conference, sponsored by the National Eye Institute Bethesda, Md 10–11 September 1979; Vol 2, No 7.
4. Sanders D. Intraocular lens power calculations: Techniques and results in: WJ Stark, A. C. Terry, AE Maumenee's (ed). Anterior segment surgery (IOLs, Lasers and refractive keratoplasty) Baltimore: Williams and Wilkins, 1987: 37–47.
5. Thomson J. Intraocular lens power calculations: Critical evaluation of different techniques. In W. J. Stark, AC. Terry, AE. Maumenee's (ed): Anterior segment surgery (IOLs, Lasers and refractive keratoplasty). Baltimore: Williams and Wilkins, 1987; 31–6.