J. N. Crossley, C. J. Ash, C. J. Brickhill, John C. Stillwell, N. H. Williams.
What is Mathematical Logic?.
OUP. 1972
This stimulating introduction draws together in a readable form
the major issues and recent developments of modern mathematical logic.
Gödel’s theorems, computability and recursive functions,
and consistency and independence in axiomatic set theory, are all clearly explained.
Both the non-logician and the reader embarking on serious study of the subject
will find this book invaluable.