The text is the same that we have used for several semesters. There
are a couple of different versions of the 9th edition (see below).
Elementary Differential Equations and Boundary Value Problems,
by William Boyce and Richard DiPrima (9th Edition)
TEXT NOTE: If you're getting this on
your own, you may choose to get the version without Boundary Value
Problems (only a few dollars difference). Links on Amazon.com: