Akhavansepahy, abbas, Shojaibagheni, ghazaleh, khavarinejad, ramezanali, khajeh, khosro (2011) ‘Study of the ability of producing vitamin B12 by Bacillus megaterium PTCC1250 and optimizing the production conditions’, Iranian Journal of Biological Sciences, 5(4), pp. 43-51. doi: