Borkan JM.
Med Health R I. 2004 Nov;87(11):328-30.
PMID: 15631297

Melguizo Jiménez M.
Aten Primaria. 2009 Nov;41(11):587-9. doi: 10.1016/j.aprim.2009.09.004. Epub 2009 Sep 25.
PMID: 19781817

Clark RM.
J Med Assoc Ga. 2008;97(3):16-7.
PMID: 19044080

Smith CW.
Am Fam Physician. 1989 May;39(5):36, 48, 52.
PMID: 2718902

Bowman MA, Neale AV.
J Am Board Fam Med. 2014 May-Jun;27(3):303-5. doi: 10.3122/jabfm.2014.03.140088.
PMID: 24808105