The Georgian GM Lasha Janjgava has produced a fantastic text on the QGD and Catalan for black. The book is worth buying for its coverage of the Catalan alone, though it also includes whole chapters with theory and game fragments for most variations of the Queen’s Gambit Declined, including the Tartakower, the Exchange, and the popular Lasker Defense, which Anand has been using to great effect against Topalov recently.
The book is typical fare for Gambit, which is to say it has a fantastic layout, thorough and complex coverage of mainlines and sidelines supported by game fragments with sufficient explanatory prose to clue the reader into the plans behind certain moves. In a mere 18 pages, Janjgava gives a nice repertoire for black in both the open and closed catalan, covering the main ideas for white and how black should meet them. Overall, I have found that the QGD can be a very forgiving opening compared to the slav or meran semi slav, and if you have the philosophy of solidity first with black, than this book should appeal to you. Below, I’ve included some of the fantastic games by Anand in the lasker defense recently.