Mosasaur monographs (sorry)

[Jeffrey Martz <jeffmartz@earthlink.net>]

     I'm know I'm way off subject, but if anyone can direct me to some antique 
science book dealers who might have the following, I would be very grateful.  
Please respond off list:

Williston, S.W. 1898. Mosasaurs. University Geological Survey of Kansas 
4:83-221.

Cope, E.D. 1875. The Vertebrata of the Cretaceous Formations of the West. U.S. 
Geological Survey of the Territorries Report 2:1-303.

     Copies of Williston's monograph are supposed to be availible for perhaps 
$50.00-$100.00.  I expect the Cope monograph is considerably harder to get.

LN Jeff