Detection of Epstein-Barr virus and human cytomegalovirus in blood and oral samples: comparison of three sampling methods - Imbronito, Ana Vitória; Grande, Sabrina Rosa; Freitas, Nivea Maria de; Okuda, Osmar; Lotufo, Roberto Fraga Moreira; Nunes, Fábio Daumas (Journal of Oral Science, 2008)