RT Journal Article SR Electronic T1 The Variable Roentgenographic Appearance of Invagination of the Esophagus JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 35 OP 37 VO 33 IS 1 A1 Walker, Barry Q. YR 1966 UL http://www.ccjm.org/content/33/1/35.abstract AB