https://www.b12d.org/book/export/html/1502

http://www.discoveriesinmedicine.com/To-Z/Vitamin-B12.html

http://www.dailymail.co.uk/health/article-2191161/The-60p-injection-boost-flagging-energy.html

http://www.thejournal.co.uk/news/north-east-news/horden-gp-dr-joseph-chandy-4416898

http://shevlinsebastian.blogspot.in/2010/12/magic-vitamin.html

http://articles.economictimes.indiatimes.com/2012-01-08/news/30602259_1_needy-patients-deficiency-blood-tests

http://bebrainfit.com/vitamin-b12-deficiency-brain/

http://brainblogger.com/2014/07/30/vitamin-b12-deficiency-and-its-neurological-consequences/

http://kellybroganmd.com/article/b12-deficiency-brain-health/

http://well.blogs.nytimes.com/2013/12/10/acid-suppressing-drugs-linked-to-vitamin-b12-deficiency/

http://news.harvard.edu/gazette/1998/01.22/Red-BloodedDoct.html

http://www.wellbeingwithbrittany.com/tips-blog/2015/9/2/could-you-be-b12-deficient-the-dangers-of-b12-deficiency-what-you-need-to-know-now