Bern C, Montgomery SP, Herwaldt BL; एवं अन्य (November 2007). "Evaluation and treatment of chagas disease in the United States: a systematic review". JAMA. 298 (18): 2171–81. PMID18000201. डीओआइ:10.1001/jama.298.18.2171. Explicit use of et al. in: |author= (मदद)सीएस1 रखरखाव: एक से अधिक नाम: authors list (link)
Bern C, Montgomery SP, Herwaldt BL; एवं अन्य (November 2007). "Evaluation and treatment of chagas disease in the United States: a systematic review". JAMA. 298 (18): 2171–81. PMID18000201. डीओआइ:10.1001/jama.298.18.2171. Explicit use of et al. in: |author= (मदद)सीएस1 रखरखाव: एक से अधिक नाम: authors list (link)