1. La Raza Medical Center; Cornea and Ocular Surface Clinic, Ophthalmology Department; Mexican Institute of Social Security (IMSS) Mexico City Mexico
2. Destellos de Luz non-profit Foundation; Cornea and Uveitis Department; Av. Lázaro Cárdenas # 2600 Ote. Col. Valle Oriente San Pedro Garza Garcia Nuevo León Mexico 66269
3. Brighton and Sussex University Hospitals; Sussex Eye Hospital; Eastern Brighton Road Brighton UK BN2 5BF
4. National Institute of Public Health; Tobacco Research Department; 7a Cerrada de Fray Pedro de Gante #50 Col Seccion XVI, Tlalpan Mexico City Mexico City Mexico 14000
5. Johns Hopkins Bloomberg School of Public Health; Department of Epidemiology; 615 North Wolfe Street, Mail Room E6132 Baltimore Maryland USA 21205