Sometimes I feel that all the best business literature has been written in the 90's. Since then, it's mostly about slapping things on top and trying to be original, while looking back at the foundations like the Technology Adoption Lifecycle in Marketing is something that should definitely be done a lot more.
Other good recommendations if you talk about the 90’s and 80’s is SPIN Selling from Neil Rackham. It just cuts through a lot of crap and mumbo jumbo out there today. From marketing & sales I also liked the engineer-perspective on it by Mark Roberge (Sales Acceleration Formula). This one is a LOT more modern though. Thank you for sharing!