Não informado. (1990). The British journal of general practice. Royal College of General Practitioners.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. The British Journal of General Practice. London: Royal College of General Practitioners, 1990.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. The British Journal of General Practice. Royal College of General Practitioners, 1990.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.