Dewulf, B., Neutens, T., Van Dyck, D., De Bourdeaudhuij, I., Broekx, S., Beckx, C. and Van de Weghe, N. 2016. Associations between time spent in green areas and physical activity among late middle-aged adults. Geospatial Health. 11, 3 (Nov. 2016). DOI:https://doi.org/10.4081/gh.2016.411.