Cross-border investigation of a Shigella sonnei outbreak in a group of Norwegian tourists after a trip to Russia Schimmer, B and Meldal, H and Perederij, N G and Vold, L and Petukhova, M A and Grahek-Ogden, D and Nygård, K, Eurosurveillance, 12, 701 (2007), https://doi.org/10.2807/esm.12.04.00701-en