1. A study of ringed hair;Cady;Arch. Derm. Syph., Chicago,1922
2. Ringelhaare in der familie E;Ehrhardt;Münch. med. Wschr,1932
3. Ueber Veränderungen des Pigment- und Luftgehaltes im Ringelhaar;Hoepke;Z. ges. Anat,1921
4. On a remarkable alteration in appearance and structure of the human hair;Wilson;Proc. Roy. Soc,1867