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The newspaper subscriptions at the UML library are research, rather than browsing, versions of the publication; in other words, the links won't take you to the paper's website, but to a searchable database. This does not mean you won't find the articles you want; in most cases you will have access to the most recent issues of these papers.
To find articles from the Washington post start at the library home page, choose Databases from the list at left, click N, and click on Nexis Uni.
On the Nexis Uni landing page choose the tab called A Publication at the left, as illustrated below.
Type a keyword in the left hand search box on the succeeding page (shown below) and The Washington Post in the right hand box prompting for Publication name. Choose Washington Post from the dropdown, as below.
The screencast below will give some tips on filtering your search to get the articles you want.