In other Steam news, Portal: First Slice – the official demo for the title named Game of the Year by over 30 publications – is now available for free to all gamers via Steam.
Valve, 2008. május 8. (Hozzáférés: 2013. január 25.) „In other Steam news, Portal: First Slice -- the official demo for the title named Game of the Year by over 30 publications -- is now available for free to all gamers via Steam.”