Woops, I meant underside-upperside. xD Or whatever you call the top.
And okay. Details then. :D
For the head I'd like a clear view of the four tines coming from his cheeks. You only need to show one side, but tines are a must. One on his head, above his eye ridge or so, and three gradually shrinking spines on his jaw bone or whatever it's called.
The dragon himself is very muscular, much like what Ping drew. You don't have to draw scales, as they aren't important. Traditional European or Western dragon so four legs, two wings, horns and a tail. His legs are not visible in the reference but imagine them to be fairly long -not gawky, long, and muscular. He's not muscle-bound or anything but he's not skinny. Sorry if this part is a bit confusing.
For the eye you can just draw the eye or a bit of the head around it. Whatever looks best and is easiest. His eyes are green-yellow and have cat pupils. In fact, this picture here is a great example:
If the wings could go at the bottom, stretching across the ref sheet, that would be great. They're standard bat/dragon wings, with three or four limbs sticking out the hold the webbing. The top is going to be patterned, which it wasn't in Ping's picture. They'll be the pattern of this here butterfly: http://www.flickr.com/photos/dawnashley/2533740559/
I'm unsure of the species and I'm sorry about that. Hopefully that's a good enough reference?
Underneath the membrane is more maroon in colour, darker from the usual red of the dragon.
This dragon also has long spines going down his back. There are about four, growing smaller until they hit his haunches, and begin after where his wings connect. They're just plain tines, not very long nor gaudy.
Hope that's enough detail! Just ask me if you need any clarification. <3