Books like The Pragmatics of Politeness
Geoffrey Leech
The Pragmatics of Politeness is 368 pages, about 6 hours 45 minutes at 250 words a minute.
7 books to read next
How long each takes
Syntactic Structures 2.2 h 
Introduction to Theoretical Linguistics 9.5 h 
Aspects of the Theory of Syntax 5.1 h 
Morphology 6.9 h 
Lectures on Government and Binding 6.8 h 
Language 10.4 h 
The Logical Structure of Linguistic Theory 10.9 h Bar height shows length. Estimated at 250 words a minute.