Tapiainen T, Prevots R, Izurieta HS, Abramson J, Bilynsky R, Bonhoeffer J, Bonnet MC, Center K, Galama J, Gillard P, Griot M, Hartmann K, Heininger U, Hudson M, Koller A, Khetsuriani N, Khuri-Bulos N, Marcy SM, Matulionyte R, Schöndorf I, Sejvar J, Steele R. Aseptic meningitis: case definition and guidelines for collection, analysis and presentation of immunization safety data. Vaccine. 2007 Aug 01; 25(31):5793-802.