@techreport{US-Environmental-Protection-Agency-EPA-2010-4073,
  author = {US Environmental Protection Agency (EPA)},
  title = {Nonroad Engine Population Estimates},
  institution = {US Environmental Protection Agency (EPA)},
  year = {2010},
  month = {jul},
  number = {NR-006e},
  url = {https://www.google.com/url?sa=i&source=web&rct=j&url=https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey%3DP10081T6.TXT&ved=2ahUKEwjpwKmxnqiUAxUdJjQIHfrCAS8Qy_kOegoIAggACAAIBxAC&opi=89978449&cd&psig=AOvVaw3Qo-wqYZt3rXd9eL5zdC-l&ust=1778279736525000},
  keywords = {Unspecified Feedstock, Gasoline, Methane (Natural Gas), Unspecified Pathway, Engine Testing and Performance, Recreational},
}