Von Scheele BG, Martin RD, Gilsenan AW, Ceberg J, Andrews EB, Masica D, Alvegård T. The European postmarketing adult osteosarcoma surveillance study characteristics of patients: a preliminary report. Acta Orthop. 2009;80:67-74.
Reed (Earnshaw) SJ, Reed JH. The use of statistical quality control charts in monitoring interviewers. Proceedings of the Survey Research Methods Section, American Statistical Association. 1997 Jan;893-8.