Some graphics (*.tga) are generated from following mentioned sources:

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device_background.tga

http://www.stockvault.net/photo/102984/brushed-steel-texture
Image license terms:
This photo is free for personal, educational and non-commercial usage.
You may not use it to promote a product or a service.
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nixie.tga

http://seriss.com/people/erco/unixtools/nixieclock/
GNU GENERAL PUBLIC LICENSE Version 2
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