Cochran, J.A. Ketley, C.E. Duckworth, R.M. Van Loveren, C. Holbrook, W.P. Seppä, L. Sanches, L. Polychronopoulou, A. O'Mullane, D.M., Development of a standardized method for comparing fluoride ingested from toothpaste by 1.5-3.5-year-old children in seven European countries. Part 1: Field work, Community Dentistry and Oral Epidemiology, (32), 39-46, 2004, 0301-5661, 1600-0528