René Descartes books in order
9 books in the catalogue, about 29 hours of reading in all; the shortest takes 48 minutes and the longest 6 hours.
9 standalone books in the catalogue.
Standalone books
Meditations on First Philosophy 3.5 h 
A Discourse on Method 3.1 h 
The Principles of Philosophy 4.1 h 
Descartes 5.0 h 
Philosophical Writings 5.6 h 
Rules for the Direction of the Mind 1.7 h 
The Passions of the Soul 3.0 h 
Discourse on the Method for Conducting One's Reason Well and for Seeking Truth in the Sciences 48 min Discourse on Method and Meditations on First Philosophy, 4Th Ed 2.2 h