Horton PS.
J Am Coll Dent. 1978 Apr;45(2):111-9.
PMID: 274480

Cassingham RJ.
LDA J. 1987;46(1):35.
PMID: 3472022

Epstein G.
J Conn State Dent Assoc. 1976 Jan;50(1):5-8.
PMID: 815298

Field R.
Nurs Stand. 1999 Sep 1-7;13(50):63. doi: 10.7748/ns.13.50.63.s60.
PMID: 10661214

de Winter F.
Ned Tijdschr Tandheelkd. 2011 Jun;118(6):296; author reply 296.
PMID: 21761791

Karimbux NY.
J Dent Educ. 2014 Apr;78(4):511.
PMID: 24706679

Gerbert B.
J Dent Educ. 1986 Oct;50(10):585-93.
PMID: 3463597