Willén R.; Carlén B.; Wang X.; Papadogiannakis N.; Odselius R.; Wadström T. Morphologic Conversion of Helicobacter Pylori from Spiral to Coccoid Form: Scanning (SEM) and Transmission Electron Microscopy (TEM) Suggest Viability: Scanning (SEM) and transmission electron microscopy (TEM) suggest viability. Upsala Journal of Medical Sciences, v. 105, n. 1, p. 31-40, 12 Jul. 2000.