Natural gas appliances
, , , , , and . "Results of the California Healthy Homes Indoor Air Quality Study of 2011–2013: impact of natural gas appliances on air pollutant concentrations." Indoor Air 26 (2016).
, , , , , and . "Results of the California Healthy Homes Indoor Air Quality Study of 2011-2013: Impact of Natural Gas Appliances on Air Pollutant Concentrations." Indoor Air (2015).