title: Comment on "Fossil Fuel Combustion-Related Emissions Dominate Atmospheric Ammonia Sources during Severe Haze Episodes: Evidence from15N-Stable Isotope in Size-Resolved Aerosol Ammonium".
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Nanjing University of Information Science and Technology , Nanjing 10044, China.
authors.forename: Yunhua
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Nanjing University of Information Science and Technology , Nanjing 10044, China.|School of Environmental Science and Engineering, Shaanxi University of Science and Technology , Xi'an, Shaanxi 710021, China.
authors.forename: Hongrui
authors.initials: H
authors.lastname: Ma