I found several inquiries about the good ol' AmigaDOS Online Reference Manual on this forum. The site no longer exists but there's a snapshot of it archived in the Wayback Machine. Some people tried to get an offline copy of the snapshot to no avail – it appears to be difficult to download pages from the Wayback Machine with web crawlers and online content retrievers like Wget or HTTrack Website Copier. The programs seem to mess up lots of links and they may also fail to download lots of pages for some reason. That's why there are services designed for this purpose (like Wayback Downloader) but they do not seem to be free of charge, and you would also have to trust them with your credit card or PayPal information.
I don't know if anyone is interested but here's an offline copy of the AmigaDOS Online Reference Manual (see the attachments & the DL link). I fixed the links in the .htm files by using some scripts but I had to do some of the stuff entirely manually.
The .zip containing the separate .htm files is slightly better than the compiled Microsoft HTML Help file (.chm) which displays some errors messages when e.g. clicking on the National Amiga logo on the start page. Please feel free to use the separate files to create a better HTML Help file if you want. The start page is "Start.htm".
I omitted some pages that seemed unnecessary (e.g. the Gateway2000 INC. page) and I did not want to include some programs that were outdated (e.g. the ones available on the TCP Stacks and Dialers page or FTP Programs page). I believe the most recent versions of those programs are available on Aminet. Moreover, there were several pages that were not collected by the web crawlers that are used by the Internet Archive. Those pages might be lost for good.
Separate files:
AmigaDOS_Online_Reference_Manual_(Bare).rar
Checksum:
Checksum_(Bare).rar
MS HTML Help (.chm):
http://s000.tinyupload.com/?file_id=99583362508006172111
Checksum (.chm):
http://s000.tinyupload.com/index.php...45521091031330