The quiet that comes when work slows for the the holidays is a good time to catch up on the best marketing resources of the past year. Here are three that I recommend:
101 Examples of Effective Calls to Action from Hubspot. Full of useful examples for presenting an eye-catching, action-motivating call to action on a webpage. Although largely focused on the visual presentation of call to action buttons and links, copywriters who work with a designer on web content can also learn new techniques from this guide.
Blueprint of a Modern Marketing Campaign from Kapost. The concept of "content pillars" presented in this book is a particularly useful way to look at content planning and production activity. Also provides ideas on how to organize content teams and worksheets to begin your planning.
Mind of the Engineer study from UBM. If your marketing targets technical decision-makers, you'll want to read these insights about how engineers use information sources when looking for new products and vendors.