About Barrett's

Pages specifically describing Barrett's Oesophagus (UK) / Barrett's Esophagus (US):
(Many have downloadable information.)

http://www.learnaboutbarretts.com/what-is-barretts-esophagus.html
Images above courtesy of Medtronic whose page on Barrett's Esophagus may be accessed by clicking on them.

Past, Present & Future of Barrett's Oesophagus A position paper published by 

MRC Cancer Unit, University of Cambridge, February 2017