if i put a link on my blog that sends visitors to other websites?

[Mark]

to wikipedia and other high ranking websties, how will it help my blog with the search engines?

[webmaster]

there is no chance or no advantage if you give link to others, until they give link to you.
If you copy content from them, then you need to give link definitely so that you going to be free from copy content issues.

[Rob]

no,,it not works, untill these other websites will provides links to your site..

[Rachael]

It wont. Who told you that ???