Thorsdottir , I., Gunnarsdottir , I., Ingolfsdottir , S. E. and Palsson , G. (2006) “Fruit and vegetable intake: vitamin C and beta-carotene intake and serum concentrations in six-year-old children and their parents”, Food & Nutrition Research, pp. 71-76. doi: 10.3402/fnr.v50i2.1561.