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The requested URL /bookmarks/mark?op=add&bkmk=http%3A//science.sciencemag.org/content/61/1587/562&title=A%20PROPOSAL%20FOR%20SUMMER%20SESSIONS%20OF%20THE%20AMERICAN%20ASSOCIATION%20AT%20ITHACA%20IN%201926 was not found on this server. That’s all we know.