TY  - RPRT
TI  - Frictional forces in fixed appliances.
AU  - D C Tidy
PY  - 1989
DO  - 10.1016/0889-5406(89)90462-9
UR  - https://pubmed.ncbi.nlm.nih.gov/2773871/
ID  - 2773871
ER  -