How can i extract subs that seemingly do not exist? - VideoHelp Forum
How to merge a subtitle file with an MKV video (fast way)
GitHub - iPzard/mkvtoolnix-batch-tool: Batch video and subtitle processing program with the ability to add, remove, or extract subtitles from all video files in a directory and its sub-directories.
Mayuresh Kadu's techie blog: Extracting Subtitles from a MKV
ffmpeg - How to remux MP4/MKV files using GUI? - Ask Ubuntu