One of the open questions I had with my Angular Grails project was how testing was going to work and I came up with a solution that I'm pretty satisified with.
This month includes a classic Groovy book as well as yet another AngularJS book.
Grails and AngularJs are two incredible frameworks and with the newer REST features of Grails they can be a pretty nice pairing. That isn't to say that there isn't some work involved in getting them to play well together though.
This month includes an excellent book about Groovy along with a decent but mildly insulting book on SASS.