Eight Centuries (formerly 19th Century Masterfile)

A vast "Index of Indexes", and is the largest resource for historical research prior to 1925.

19th Century Masterfile brings together over 60 subject indexes to: Periodicals; Newspapers; Books; US Congressional Record; US and UK Government Documents;US Patents. You can query over 11 million citations in 19th Century Masterfile in a single search.

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