@article{hoornweg2016an,
  title = {An Urban Approach to Planetary Boundaries}
  author = {Hoornweg, Daniel and Hosseini, Mehdi and Kennedy, Christopher and Behdadi, Azin},
  journal = {Ambio: A Journal of the Human Environment},
  doi = {10.1007/s13280-016-0764-y},
  year = {2016}
}