There are pros and cons to all of the above, and there will probably never be a right answer.
The <ref> and <references> tags creates what most people would call "footnotes"
I treat footnotes different from source citations. But the lines are blurred. My inline footnotes tend to be short references that point to the larger, more complete source citations.
One disadvantage of putting the full citation inline, is it makes the text, in edit mode, too difficult to read and maintain.
I recently saw a clever implementation that used named refs before defining them, then defining them at the end. It had the unfortunate side effect of a list of linked numbers at the start of the sources section, which was then hidden by wrapping the section with a span tag. This kept the bio section easy to read and maintain in edit mode, while keeping all the full citations together in the sources section.