1. Fijten GH, Blijham GH, Knottnerus JA. Occurrence and clinical significance of overt blood loss per rectum in the general population and in medical practice. Br J Gen Pract 1994;44:320-5.
2. Fijten GH. Rectal bleeding, a danger signal? Dissertation. Maastricht: Universiteit Maastricht, 1993.
3. Okkes IM, Oskam SK, Lamberts H. Van klacht naar diagnose: Episodegegevens uit de huisartspraktijk. Bussum: Coutinho, 1998.
4. Crosland A, Jones R. Rectal bleeding: Prevalence and consultation behaviour. BMJ 1995;311:486-8.
5. Consten EC, Fockens P, Reeders JW, Lanschot JJ van. Acute hemorrhage from the lower digestive tract: a search for the source. Ned Tijdschr Geneeskd 1998;142:2497-501.