Business
Buy Back Your Time, by Dan Martell

Business
Million Dollar Weekend, by Noah Kagan

Business
Rework, by Jason Fried and DHH

Customer Development
The Mom Test, by Rob Fitzpatrick

Product positioning
Obviously Awesome, by April Dunford

SAAS
The SAAS Playbook, by Rob Walling

Marketing
Traction, by Gabriel Weinberg and Justin Mares

Marketing
100M Offers, by Alex Hormozi

Sales
Founding Sales, by Mark Roberge

Deploy Empathy
Deploy Empathy, by Michele Hansen