Chabasińska, M., Przysławski, J., Lisowska, A., Schlegel-Zawadzka, M., Grzymisławski, M. and Walkowiak, J. (2007) “Serum vitamin B12 and folic acid concentrations in vegetarians”, European Journal of Clinical and Experimental Medicine, 5(4), pp. 360–364. Available at: https://journals.ur.edu.pl/ejcem/article/view/13312 (Accessed: 16 July 2026).