All icons come from Open Game Art (art by onyum.com, comissionned by Bart Kelsey)
released under CC-BY-SA 3+
* options_players & random_kart were tweaked by Marianne Gagnon


Except :
main_*.png icons, hourglass, back, back_addons, next_addons, package.png
    released under Creative-Commons BY-SA 3, By yeKcim (Anthony Carré)

mode_tt, released under Creative-Commons BY-SA 3, incorporatings artwork from yeKcim and onyum.com

tutorial.png    by Totoplus62, released under CC-BY-SA 3.0

Logo and Logo_slim : under CC-BY-SA 3.0+ by 'rastapax'

difficulty_*.png icons, released under Creative-Commons BY-SA 3, By Conso (Constantin Pelikan)

title_font, by Marianne Gagnon (Auria), released under CC-BY-SA 3+

screen*.png, by Marianne Gagnon (Auria), including elements from the public domain Tango icon set

Gauge and bar by Dakal, released under CC-BY-SA 3

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Glass Skin by Auria, under CC-BY-SA 3+
except background, under CC-BY-SA, by 'elisee'