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Supplementary data ml http://rspb.royalsocietypublishing.org/content/suppl/2009/02/12/272.1581.2627.DC1.ht "Data Supplement" References http://rspb.royalsocietypublishing.org/content/272/1581/2627.full.html#related-urls Article cited in: http://rspb.royalsocietypublishing.org/content/272/1581/2627.full.html#ref-list-1 This article cites 51 articles, 4 of which can be accessed free Email alertin...

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These include: References http://jech.bmjjournals.com/cgi/content/full/59/5/342#BIBL This article cites 18 articles, 4 of which can be accessed free at: Rapid responses http://jech.bmjjournals.com/cgi/eletter-submit/59/5/342 You can respond to this article at: service Email alerting top right corner of the article Receive free email alerts when new articles cite this article sign up in the box ...

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