Here's something that can make a blog, website, or Google Doc look unprofessional. It's when someone who wants to acknowledge a source merely lists the URL. So I'm reading along and at the bottom of the page I see:
Compare that to this:
McKibben, Bill. (2011) The Era of Small and Many. Orion Magazine.
Now I can see at a glance who wrote it, when it was published, and where it was published. I can still click through to see the article if I want, but it's MUCH easier for me to see if your list of sources looks credible.
Here's one way to do internal citation on the internet:
According to author and activist Bill McKibben, the number of family farms in the United States has declined over the last 150 years.
Instead of using parenthesis or a footnote, you can add a hyperlink to the text. Not all journals use this -- many will still want the traditional kind of citation, but if it's your blog or Google Doc, you can choose how you want to do it.
I think it's great that every single group is making sure they acknowledge their sources. One way to make sure your blog or Google Doc looks professional is to check to make sure you've created hyperlinks instead of just listing the URL.