Summoning Demons

Recently I've been very interested in sigils and sigil magic.  It just so happens that when browsing some darker areas of the Internet in the wee hours of the morning I stumbled upon an image file containing 99 sigils.  Ninety of these are specific to particular demons, apparently.  The remaining nine have more general purposes.

I don't typically dabble with spirits or demons but I thought this might be relevant to the interests of my readers.  Whether you choose to work with this is up to you.  I thought I recognized some of these names and symbols from somewhere but I've searched my books as well as the Internet and the closest I can turn up is this image, apparently found in a number of places on the Net besides the place I got it from.  Some of these are evocative of the Keys of Solomon, but I can't find any matches.  I haven't studied Solomon's works that closely though.

For those of you that might be brave enough to try this, let me know what happens.