Croft DE, van Hemert J, Wykoff CC, Clifton D, Verhoek M, Fleming A, Brown DM. Precise montaging and metric quantification of retinal surface area from ultra-widefield fundus photography and fluorescein angiography. Osli Retina. 2014 Jul 1;45(4):312-7. doi: 10.3928/23258160-20140709-07
Reed (Earnshaw) SJ, Reed JH. The use of statistical quality control charts in monitoring interviewers. Proceedings of the Survey Research Methods Section, American Statistical Association. 1997 Jan;893-8.