20 mph speed limits are the right policy for sociability, safety, and a healthy population.

@article{Ingamells201220MS,
  title={20 mph speed limits are the right policy for sociability, safety, and a healthy population.},
  author={Sarah Ingamells and Angela Elizabeth Raffle},
  journal={BMJ},
  year={2012},
  volume={345},
  pages={e6165}
}