ww1_planes_gun.ogg is a remis of tnt_explode.ogg, so bellow is the original licence and authors

Licenses of media
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Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
Copyright (C) 2014-2016 BlockMen
Copyright (C) 2014-2016 ShadowNinja
Copyright (C) 2015-2016 Wuzzy
Copyright (C) 2016 sofar (sofar@foo-projects.org)
Copyright (C) 2018 paramat

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====================================================

CC0 1.0 Universal (CC0 1.0) Public Domain Dedication 
for audio files (found in sounds folder)
TumeniNodes
steveygos93
theneedle.tv
frankelmedico

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