TITLE: Smith Normal Form for PIDs
QUESTION [5 upvotes]: Could someone provide a good reference to look up the existence and uniqueness of Smith Normal Form (SNF) for a PID? 

I have seen it done for Euclidean domains but not for a PIDs. I know the difference is not much, but I would like a good reference. Thanks.

REPLY [4 votes]: See Jacobson's Basic Algebra I, chapter 3. 
See also the book Finitely Generated Abelian Groups and Similarity of Matrices over a Field by Christopher Norman.