Gastric Outlet Obstruction due to an Iatrogenic Cause in a Neonatal Period – Report of Two Cases - Kosiak, W.; Swieton, D.; Fryze, I.; Aleszewicz-Baranowska, J.; Duklas, M.; Chojnicki, M. (Ultraschall in der Medizin - European Journal of Ultrasound, 2009)