Plowman N.
Radiography. 1974 Jan;40(469):2.
PMID: 4810258

Jenkins R, Baingana F, Ahmad R, McDaid D, Atun R.
Ment Health Fam Med. 2011 Jun;8(2):83-6.
PMID: 22654970

[No authors listed]
Lancet. 1970 Jan 10;1(7637):76.
PMID: 4188636

Bentley HB, Channon BT, Walker W.
Radiography. 1978 Mar;44(519):81-4.
PMID: 635159

[No authors listed]
Radiography. 1978 Nov;44(527):253-4.
PMID: 734069

Augustus S.
Nurs Mirror Midwives J. 1971 Dec 10;133(24):37-9.
PMID: 5210101

Wilde AA, van den Brink RB.
Neth Heart J. 2005 Feb;13(2):67-83.
PMID: 25696454