R. Talaie, H. Zojaji, D. Mirsattari, A. Kaboli, A. H. Mohammad Alizadeh, and M. R. Zali, “Comparison of two different eradication regimens for H. pylori: amoxicillin, metronidazole, bismuth and omeprazole (OMAB) versus the new regimen of penbactam, clarithromycin and omeprazole (OPC); a randomized clinical trial”, Gastroenterol Hepatol Bed Bench, vol. 1, no. 3, Jun. 2009.