Tsai, W., McHale, M., Jennings, V., Marquet, O., Hipp, J., Leung, Y. & Floyd, M. (2018). Relationships between characteristics of urban green land cover and mental health in U.S. metropolitan areas. International Journal of Environmental Research and Public Health, 15 (2), 1-12. https://doi.org/10.3390/ijerph15020340