http://www.cdc.gov/ncidod/dpd/parasites/diarrhea/factsht_chronic_diarrhea.htm information from the Centers for Disease Control and Prevention (CDC)

http://www.vh.org/adult/provider/familymedicine/FPHandbook/Chapter05/04-5.html information from the University of Iowa's virtual hospital

http://www.cdc.gov/ncidod/dpd/parasites/giardiasis/factsht_giardia.htm information from the Centers for Disease Control and Prevention (CDC)

http://www.nlm.nih.gov/medlineplus/giardiainfections.html information from MedlinePlus

http://www.aids.org/atn/a-133-01.html information from AIDS.org

http://www.cdc.gov/ncidod/hip/INFECT/cdad.htm information from the Centers for Disease Control and Prevention (CDC)

http://www.vh.org/adult/provider/familymedicine/FPHandbook/Chapter05/10-5.html information from the University of Iowa's virtual hospital

http://www.healthlink.mcw.edu/article/930591431.html information from the Medical College of Wisconsin's HealthLink

http://digestive.niddk.nih.gov/ddiseases/pubs/whipple/ information from the National Digestive Disease Information Clearinghouse