{"id":"lefevre2009observed","DOI":"10.1038/nature08228","URL":"https://doi.org/10.1038/nature08228","type":"article-journal","title":"Observed variations of methane on Mars unexplained by known atmospheric chemistry and physics","author":[{"given":"Franck","family":"Lefèvre"},{"given":"François","family":"Forget"}],"issued":{"date-parts":[[2009]]},"year-text":"2009","container-title":"Nature 460(7256), 720–723","catalog-key":"SRC0D7EXKPJ0M3K"}