Using content that has no apparent source

[scyzoryk]

You've all seen it.

-widget quotations
-widget facts
-widget humour

These have been plastered all over the net with no apparent author, source, or copyright, and can be seen on a billion different web pages.

Would you use it on your site if it appealed to the right audience?

[VegasRook]

Do some research and find the source or use at your own peril.

No, I would not use something that has no source. Not too many things in life are source-less.

For example,

1 in 3 women are the victim of domestic abuse.

What is the source? If you can't find it, the fact/stat is worthless so why use it.