Definition: Given a document, generate a short title of the document. The title should convey the main idea/event/topic about which the document is being written. Note that URLs in the text have been replaced with [Link].
Input: Story highlights Mueller  sent a notice  called a document preservation request  to White House staff
(CNN)  Special counsel Robert Mueller  has asked the White House to preserve all documents relating to the June 2016 meeting at Trump Tower that Donald Trump Jr.  Jared Kushner and Paul Manafort had with a Russian lawyer and others  according to a source who has seen the letter.
 Mueller  sent a notice  called a document preservation request  asking White House staff to save "any subjects discussed in the course of the June 2016 meeting" and also "any decisions made regarding the recent disclosures about the June 2016 meeting " according to the source  who read portions of the letter to CNN.
The letter from  Mueller  began: "As you are aware the Special Counsel's office is investigating the Russian government's efforts to interfere in the 2016 presidential election  including any links or coordination between the Russian government and individuals associated with the campaign of Donald Trump. Information concerning the June 2016 meeting between Donald J Trump Jr and Natalia Veselnitskaya is relevant to the investigation."

Mueller asks WH to preserve info from Trump Jr. meeting