Owing to the fact that a Living Reviews in Landscape Research article may evolve over time, we recommend to cite the article as follows:
Guido Van Huylenbroeck and Valerie Vandermeulen and Evy Mettepenningen and Ann Verspecht,
"Multifunctionality of Agriculture: A Review of Definitions, Evidence and Instruments",
Living Rev. Landscape Res. 1, (2007), 3. URL (cited on <date>):
The date given as <date> then uniquely identifies the version of the article you are referring to.