Ronald Wardhaugh
An introduction to sociolinguistics
English for a Changing World Level 1 Student Book
English for a Changing World Level 1 Cue Book
Introduction to linguistics
An Introduction to Sociolinguistics
English for a changing world--Cue book 2
Introduction to Sociolinguistics
English for a Changing World Level 1 Listening Comprehension Manual
English for a Changing World Level 4 Listening Comprehension Manual
English for a Changing World
How conversation works
Language & nationhood