Rockwood NJ, Jeon M. Estimating complex measurement and growth models using the R package PLmixed. Multivar Behav Res. 2019 Mar;54(2):288-306. doi: 10.1080/00273171.2018.1516541
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