Can some one give me an example with footnote when one sentence has the same source?

Like I'm using an article from the internet and my first sentence is using that article for its source, my second sentence is using another source(a book), and my last sentence is using the same source as the first sentence.....how do i write that?Can some one give me an example with footnote when one sentence has the same source?
Can you tell us exactly what you've said, so we can comment intelligently.