Forgotson EH, Forgotson J.
Med Care. 1970 Jan-Feb;8(1):3-14. doi: 10.1097/00005650-197001000-00002.
PMID: 5417721

[No authors listed]
BMJ. 1991 Jul 27;303(6796):244-6.
PMID: 1884066 Free PMC Article
Free PMC Article

Rouse MO.
JAMA. 1968 May 13;204(7):623. doi: 10.1001/jama.204.7.623.
PMID: 5694493

Buzek J, McNamara M.
J Med Educ. 1968 Nov;43(11):1197-9. doi: 10.1097/00001888-196811000-00016.
PMID: 5697404

Milne RM.
Br Med J. 1978 Oct 28;2(6146):1232. doi: 10.1136/bmj.2.6146.1232-a.
PMID: 719370 Free PMC Article
Free PMC Article

Thatcher PG.
BMJ. 1991 Sep 21;303(6804):721-2. doi: 10.1136/bmj.303.6804.721-d.
PMID: 1912936 Free PMC Article
Free PMC Article

Gomez EC.
J Am Acad Dermatol. 1980 Jun;2(6):535-6. doi: 10.1016/s0190-9622(80)80164-2.
PMID: 7400414