Vidal-Alaball, J; Butler, CC; Cannings-John, R; Goringe, A; Hood, K; McCaddon, A; McDowell, I; Papaioannou, A (20 July 2005). “Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency.”. The Cochrane database of systematic reviews (3): CD004655. doi:10.1002/14651858.CD004655.pub2. PMID16034940.
Lachner, C; Steinle, NI; Regenold, WT (2012). “The neuropsychiatry of vitamin B12 deficiency in elderly patients.”. The Journal of neuropsychiatry and clinical neurosciences24 (1): 5–15. doi:10.1176/appi.neuropsych.11020052. PMID22450609.
Vidal-Alaball, J; Butler, CC; Cannings-John, R; Goringe, A; Hood, K; McCaddon, A; McDowell, I; Papaioannou, A (20 July 2005). “Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency.”. The Cochrane database of systematic reviews (3): CD004655. doi:10.1002/14651858.CD004655.pub2. PMID16034940.
Lachner, C; Steinle, NI; Regenold, WT (2012). “The neuropsychiatry of vitamin B12 deficiency in elderly patients.”. The Journal of neuropsychiatry and clinical neurosciences24 (1): 5–15. doi:10.1176/appi.neuropsych.11020052. PMID22450609.