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* http://www.pentrace.net/article092801120.html A  ''Pen Trace'' article

* http://www.columbuspenne.it Official web site, containing interesting infos

* [http://web.archive.org/web/20101128025934/http://pentrace.net/article092801120.html] A  ''Pen Trace'' article

* http://www.italianfountainpenacademy.it/storia/columbus.htm a brand history

* [https://web.archive.org/web/20180830144013/http://columbuspenne.it/storia-it.html] The website of the company that had bought the trademark, inside there are various interesting historical information

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