https://www.reddit.com/r/Doom/comments/42877v/cant_extract_audio_out_of_a_doom_wad_file/ http://www.terrybutler.co.uk/tools/doom-engine-wad-reader-and-extractor/ https://code.google.com/archive/p/unwad/ http://slade.mancubus.net/ (http://doom.wikia.com/wiki/SLADE)
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