Springer offers a 20% discount on R books ordered via the books webpage
at Springer.com.  To get this discount, click on "Publisher Info."  At
the Springer web site, click on the shopping cart, proceed to checkout,
log in, and enter the following SpringerToken without blanks on the
registration formula.  The SpringerToken is: pR7e7JnXENtXYPP.  You will
have to register as a Springer customer the first time you order.