RT Journal Article SR Electronic T1 Vitamin B12 deficiency (July 2015) JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 15 OP 15 DO 10.3949/ccjm.83c.01001 VO 83 IS 1 A1 Phillips, Kenneth R. YR 2016 UL http://www.ccjm.org/content/83/1/15.1.abstract AB