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6Bor, MV., et al; A daily intake of approximately 6 microg vitamin B-12 appears to saturate all the vitamin B-12-related variables in Danish postmenopausal women. (2006) Am J Clin Nutr. Jan;83(1):52-8.

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9Hvas, A., et alThe effect of recombinant human intrinsic factor on the uptake of vitamin B12 in patients with evident vitamin B12 deficiency. (2006) Haematologica. Jun;91(6):805-8.

10Data on File. Subset Analysis of 6 subjects with IF deficiency from Hvas (2006) cohort. (Xeragenx LLC.)

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13Workinger, JL., et al; Systemically Administered Plant Recombinant Holo-Intrinsic Factor Targets the Liver and is not Affected by Endogenous B12 levels. (2019) Sci Rep 9, 12269.

14Vortherms, AR., et al; A water soluble vitamin B12-Re(I) fluorescent conjugate for cell uptake screens: use in the confirmation of cubilin in the lung cancer line A549. (2011) Chem Commun. 47, 9792-9794.