Sorry Aldo, actually you are not exactly right on this point--

photo was sourced from wikipedia
http://en.wikipedia.org/wiki/Image:GardenED.jpg

In general, objects over 70 years old fall into the public domain and an image of such an item is effectively also public domain.

As Vint cites above: Under United States copyright law, originality of expression is necessary for copyright protection, and a mere photograph of an out-of-copyright work may not be protected under U.S.copyright law. This photograph was taken in the U.S. or in another country where a similar rule applies (for a list of allowable countries, see Commons Country-specific rules). This photographic reproduction is therefore also in the public domain.

We did not use content from their website and therefore their claims of copyright are not valid. Most websites, like ours in fact, try to throw a blanket over everything when actually only part of the content is actually theirs. While their notes about a painting would be copyright, the images are not. Text btw can be used without approval as long as it is short (I think less then 200 words?) and links back to source.

Our policy is still to give attribution to the original artist (which we did),museum and photographer if possible, but in fact is not necessary in this case.