Maresz, K. (2015). Proper calcium use: vitamin K2 as a promoter of bone and cardiovascular health. Integrative Medicine: A Clinician's Journal, 14(1), 34.
Iwamoto, J., Takeda, T., & Ichimura, S. (2000). Effect of combined administration of vitamin D3 and vitamin K2 on bone mineral density of the lumbar spine in postmenopausal women with osteoporosis. Journal of orthopaedic science, 5(6), 546-551.