RT Journal Article SR Electronic T1 Megaloblastic anemia due to severe vitamin B12 deficiency JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 8 OP 9 DO 10.3949/ccjm.89a.21041 VO 89 IS 1 A1 Candelario, Nellowe A1 Klein, Catherine YR 2022 UL http://www.ccjm.org/content/89/1/8.abstract AB