Summer vacation. For most founders of early-stage and fast-growth companies those two words together are about as foreign as snow in August. Still, summer does tend to slow down the pace somewhat.

So whether you are one of the lucky ones who's managed to negotiate a few days on the beach or you simply find yourself on a plane without Wi-Fi while traveling for work, there's no better time than the summer to catch up on some good old-fashioned reading.

Rather than fill your reading pipeline with the near endless supply of books detailing current trends and theories of modern business, why not reach back into the past for some inspiration from the classics?

These books may not mention a digital-centric marketing plan or espouse the benefits of lean methodology, but there's a reason they've survived decades: they're loaded with bedrock business advice that all entrepreneurs should have in their back pocket.

These seven books have shaped business, innovation and strategy for decades. Countless founders have based their processes, growth roadmaps and marketing strategies on them. They've stood the test of time, and are worth a read.

1. The E Myth

A business book that's turned into a business empire. If you have your MBA, chances are this was required reading at some point. In the E Myth, Michael Gerber uncovers the myths and assumptions around starting and growing a business. He details the evolution most businesses journey through from entrepreneurial infancy to the growing pains and finally to maturity. He does this all through the portrayal of the three personalities every business owner experiences: The Entrepreneur, Technician, and Manager. This iconic book is worth a read especially if you are in the early stages of growth.

2. The 7 Habits of Highly Successful People

Independence. Interdependence. Continuous improvements. Sounds a lot like making assumptions, testing with your audience and pivoting, doesn't it? The genius of this classic is that the principles outlined within it can be applied to business and life beyond it as well. Setting goals, taking it one step at a time, honing your listening skills to understand people and creating sustainable practices are all crucial components to not just a successful life, but a happy one.

3. How to Win Friends and Influence People

Dale Carnegie's 1936 masterpiece is a salesperson's bible and the first entrepreneurial book that lays the core truth right out there: in business, it's important to be liked. Critics have argued over the years that this book essentially is a guide to manipulation, but think of Carnegie's guiding principles in terms of getting to know your audience: Show respect for other's opinions, see things from a different point of view, encourage others to talk about themselves. These are the fundamentals of audience persona development that will shape your path in getting to market. The book has been updated several times, including the most recent version for the digital age.

4. Business Adventures

If Warren Buffet and Bill Gates share the same favorite business book, it should probably go right to the top of every entrepreneur's reading list. Author John Brooks was a New York journalist who compiled his long-form business profiles into this book, which is lean on advice tidbits and heavy on cautionary tales from huge corporations like Ford, General Electric and Xerox. It may mess with your mind (in the best way) to read about Ford ignoring consumer feedback or Xerox refusing to pivot into becoming an advanced technology player - and then think about how those companies recovered in the decades since.

5. Purple Cow

Okay, so this one isn't quite covered in dust yet. But Seth Godin's simply effective ideas on branding will be relevant for as long as there's clutter in the marketplace. Purple Cow is novella-sized and doesn't require a notebook to remember its most salient points, most of which are: be unique, take risks and oh, don't forget to be unique. Hopefully you've already thought about your brand messaging in a non-traditional way, but if you haven't, here's a good place to get the creative juices flowing.

6. Good to Great

In his book, "Good to Great: Why Some Companies Make the Leap...and Others Don't," author Jim Collins outlines how companies can transition from being average to great. The book explores companies that have achieved greatness and zeroes in on the factors that got them there. What are these factors? You'll have to read it to find out, but let's just say it's about getting the right people on the bus, realizing and tapping into core competencies, and discipline.

7. Atlas Shrugged

Innovators facing enormous opposition from behemoths of the status quo: the story of Rearden Steel, or Uber? No matter how you feel about Ayn Rand's philosophies, there's a lesson on the power of creativity and achievement to be learned from the story. Basically, you can't stop the train of innovation.