I find that the Wikipedia is usually a great place to start:
I doubt you'll find a reference putting these two subjects together. This piece was designed for friends who recently wed. One is a follower of the Morrigan, and the other a follower of Odin (I believe he's of the Asatru faith). The Thor's Hammer (Mjolnir) is representative of Odin, while the raven is a common symbol of the Morrigan.
Yes, it would be uncommon to find the two together...
Right after seeing this picture, actually, I went directly to Wikipedia! A good way to answer all questions.. I have a friend who is rather obsessed with Norse mythology, and seeing the Mjolnir in your picture reminded me that it was high time that I try to better understand the things he's been talking to me about! This led to several hours spent browsing many pages on Wikipedia
I keep trying to challeng myself with new textures and ideas, so I'm considering this to be a success. I've been stuck on human portraits and figures for far too long.
I appreciate the comment on the soaps too!