@article{kirchherr2017conceptualizing,
  title = {Conceptualizing the circular economy: An analysis of 114 definitions}
  author = {Kirchherr, Julian; Reike, Denise; Hekkert, Marko},
  journal = {Resources, Conservation and Recycling},
  url = {http://www.sciencedirect.com/science/article/pii/S0921344917302835},
  doi = {10.1016/j.resconrec.2017.09.005},
  year = {2017}
}