Vertebral spines on sauropods...

[Christopher Srnka <theclaw@sprintmail.com>]

I was checking out Stephen Czerkas' drawing of _Diploducus_, and
the dorsal spines in the reconstruction. I also remember seeing similar
spines on a drawing by Greg Paul of a _Brachiosaurus_ for The Dinosaur
Encyclopedia. Is it generally accepted that many sauropods had such structures?
How similar are these spines to those on, say, an _Amargasaurus_
or _Dicraeosaurus_?
-Chris Srnka