Provided here is a link to a wiki page on the Khmer Empire.

Wikipedia can be a helpful starting point when beginning research; but because anyone on the internet can edit its information, it is important to remember that it may not always be a reliable source. Scholarly, peer-reviewed sources are the best means of attaining accurate information.

Here is a link to the revision history of the wikipedia page for the oft-controversial topic of Capital punishment in the United States.