*[http://www.symbos.de SymbOS]
*[http://www.cpcmania.com/news.htm CPC Mania] - some tools like CPR tools, CPCDiskXP, CPCTapeXP - plus some technical informations
*[https://bread80.com/category/amstrad-cpc/bread80.com] - some analysis of Firmware and BASIC logic (and also the video subsystem- hardware)
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