<img src="http://www.anyurl.com/img/pic.jpg" />
But you will need to search for the URL of each picture (NOTE that one is the URL of the website but the URL that you need is the one of the picture alone, which you can find on the source of the page where the picture is displayed) and remember that if those sites adjust their folders you will need to change the source of your picture as well.
Also, usually if you update a picture it will be stored on a differente location. So you better get a copy of those pics and put them all together on the same server.