@misc{indiciaeddf009523d45,
  title = {Measuring urban problems: a brief report on rating grass coverage.},
  author = {E R Christophersen and L A Doke and D O Messmer and T R Risley},
  year = {1975},
  doi = {10.1901/jaba.1975.8-230},
  url = {https://pubmed.ncbi.nlm.nih.gov/16795496/},
  note = {Source identifier: 16795496}
}