Electronic real-time surveillance for influenza-like illness: experience from the 2009 influenza A(H1N1) pandemic in Denmark
Harder, K M and Andersen, P H and Bæhr, I and Nielsen, L P and Ethelberg, S and Glismann, S and Mølbak, K, Eurosurveillance, 16, 19767 (2011), https://doi.org/10.2807/ese.16.03.19767-en