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2. Nitrous oxide fact sheet;Compressed Gas Association,2012
3. US greenhouse gas inventory report 1990-2010;United States Environmental Protection Agency,2012
4. CGA G-8.3 Safe practices for storage and handling of nitrous oxide;Compressed Gas Association,2013
5. Nitrous oxide: a threat to personnel and global environment?;Dale;Acta Anaesthesiol Scand,1994