Quantum Theory, Groups and Representations:
An Introduction

Peter Woit

Published November 2017 by Springer.

The Springer webpage for the book is here.  The SpringerLink page is here (if your institution is a Springer subscriber, this should give you electronic access to the book, as well as the possibility to buy a $24.99 softcover version).  A web-page of errata is here.

You can also download the final draft version which has more or less identical substantive content to the Springer version.

For more information, see some blog entries.