From time to time, even the strongest copywriters begin to doubt themselves. Some feel that they are running out of fuel and can no longer make their copy relevant and approachable. Some, on the other hand, simply get tired of the craft.

Like in profession, there are countless tutorials and how-to guides on copywriting available. For copywriters seeking motivation or just a swift kick in the pants, here are four books that are sure to get them back behind the keyboard with new inspiration and insights.

The Elements of Style – Skrunk and White:  Although this book is nearly 100 years old, it still one of the best guides ever written in terms of how to properly use the English language. Any writer that has ever read its pages can tell you right away why it’s long been a staple of college composition courses.

Letters to a Young Journalist – Samuel G. Freedman:  Sure, there are vast distinctions between copywriting and journalism, but there are many core basics within this books that apply heavily to each field. Letters to a Young Journalist is written in a conversational style that is instantly warm and inviting, making it that much easier to take in the message of telling the truth, connecting with your audience, and making the reader your priority.

On Writing Well – William Zinsser:  Here’s another one found in most college comp classes. Considered one of the best books ever written on the topic of non-fiction, it not only explains what good writing can be, but how writers can mold themselves to create it.

On Writing: A Memoir of the Craft – Stephen King: even if you’re not a fan of King, this book is both a motivational force and a blunt and effective “toolbox” for the aspiring writer. When King writes about his struggles and his eventual success, he does so in a way that is relatable. And when he starts griping about the misuses of adjectives and adverbs, we as writers not only sympathize and understand, but maybe even feel a bit guilty.

If you don’t have any of these (and if you’re a copywriter, I bet you anything you have at least one of them), check them out today. It’s never too late to learn new approaches to the craft of copywriting.