• Encyclopedia Britannica Online : http://www.britannica.com

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• Roget’s Thesaurus Online : http://www.thesaurus.com

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• Lexico : https://www.lexico.com/
  • Lexico is a collaboration with Oxford Dictionary hosted by Dictionary.com offering definitions, meanings, and grammar in both English and Spanish.

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• Webster Dictionary : http://www.dictionary.com

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• University of Adelaide Library:Dictionaries, Encyclopedias and Almanacs : http://library.adelaide.edu.au/gen/dict.htm

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• Babylon - Ancient History Encyclopedia : https://www.worldhistory.org/

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• Cambridge Dictionary  : dictionary.cambridge.org

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•  Macmillan Dictonary : https://www.macmillandictionary.com/