“…established by the presence of histamine-fast achlorhydria and abnormal vitamin Bi2 absorption which was corrected by human IF (9). Each serum was tested for antibody I or "blocking" activity by the charcoal test of Gottlieb, Lau, Wasserman, and Herbert (7) and for antibody II or "binding" activity by the antiglobulin coprecipitation technique of Taylor, Roitt, Doniach, Couchman, and Shapland (10) as well as by the electrophoretic retention test of Jeffries, Hoskins, and Sleisenger (11). P.A.…”