Analysis of the short-term effect of pollen and spore exposure on allergy medication sales, Guilbert, Ariane, Simons Koen, Packeu Ann, De Cremer Koen, Hoebeke Lucie, Hendrickx Marijke, and Van Nieuwenhuyse An , 27th Conference of the International Society  for Environmental Epidemiology, 2015, São Paulo, Brazil, (2015)