1. Geometrical and mechanical laws of articulation;Bonwill;Trans Odont Soc Penn,1885
2. Determination of the normal arch and its application to orthodontia;Hawley;Dent Cosmos,1905
3. Der zahn-index in der orthodontie;Pont;Z Zahnarztl Orthop,1909
4. An examination of dental crowding and its relationship to tooth size and arch dimension;Howe;Am J Orthod,1983
5. Removable orthodontic appliances;Schwarz,1966