@techreport{david2009assessing,
  title = {Assessing Urban Forest Effects and Values}
  author = {DAVID J. NOWAK; ROBERT E. HOEHN III; DANIEL E. CRANE; JACK C. STEVENS; NY. CHERIE LEBLANC FISHER},
  url = {https://www.researchgate.net/publication/296342445_Assessing_Urban_Forests_Effects_and_Values_Chicago's_Urban_Forest},
  year = {2009}
}