When I first clicked the link: (a) no open-access logo, (b) button offering me the article for $35.95.
I did not at the time know what the open-access logo was supposed to look like, so I went back to the article, found it, and clicked the link again: (a) open-access logo, (b) article in its glory.
My guess is that in response to this article someone fixed something and the article is now properly open access.
http://www.sciencedirect.com/science/article/pii/S0168900210...
When I first clicked the link: (a) no open-access logo, (b) button offering me the article for $35.95.
I did not at the time know what the open-access logo was supposed to look like, so I went back to the article, found it, and clicked the link again: (a) open-access logo, (b) article in its glory.
My guess is that in response to this article someone fixed something and the article is now properly open access.