CO, NO&amp;lt;sub&amp;gt;x&amp;lt;/sub&amp;gt; and &amp;lt;sup&amp;gt;13&amp;lt;/sup&amp;gt;CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; as tracers for fossil fuel CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;: results from a pilot study in Paris during winter 2010
Atmospheric chemistry and physics