Two interconnected B vitamins: riboflavin and pyridoxine.

@article{Mccormick1989TwoIB,
  title={Two interconnected B vitamins: riboflavin and pyridoxine.},
  author={D B Mccormick},
  journal={Physiological reviews},
  year={1989},
  volume={69 4},
  pages={1170-98}
}