Corrigendum: Effects of Vitamin D and K on Interleukin-6 in COVID-19 - Visser, Margot P. J.; Dofferhoff, Anton S. M.; van den Ouweland, Jody M. W.; van Daal, Henny; Kramers, Cornelis; Schurgers, Leon J.; Janssen, Rob; Walk, Jona (Frontiers in Nutrition, 2022)