The `Oxford English Language Reference boxed set consists of the following four books:
1. OXFORD A-Z OF ENGLISH USAGE by Jeremy Butterfield
2. OXFORD A-Z OF SPELLING by Catherine Soanes & Sheila Ferguson
3. OXFORD A-Z OF GRAMMAR & PUNCTUATION by John Seely
4. OXFORD GUIDE TO PLAIN ENGLISH by Martin Cutts
All the four books are in a neat box and supplied as a boxed set for stacking safely.