Anaphylaxis: case definition and guidelines for data collection, analysis, and presentation of immunization safety data - Ruggeberg, JU; Gold, MS; Bayas, JM; Blum, MD; Bonhoeffer, J; Friedlander, S; de Souza, BG; Heininger, U; Imoukhuede, B; Khamesipour, A (Vaccine, 2007)