@article{Veenstra2012a,
author = "Marijke Veenstra and Astri Syse",
title = "Health behaviour changes and onset of chronic health problems in later life",
year = 2012,
journal = "Norsk Epidemiologi",
volume = 22,
number = 2,
pages = "135-142",
url = "http://www.ntnu.no/ojs/index.php/norepid/article/download/1559/1453"
}