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* We consider the central problems.  ## #  What's a Timeline? Timeline generation (TLG) is a way of representing a large amount of temporally dependent information concisely. It is query driven; we retrieve a corpus of text linked to some entity, event or other term. The canonical TLG model clusters these articles into topics or stories, selects the most important of these clusters and returns timestamped summaries. It can be seen as a generalisation of the multi-document summarisation task, where we have introduced temporal dependency and structure.