A 123 page card cover book titled "British Aircraft at War 1939-45" by Gordon Swanborough.

This is a comprehensive review which covers more than 200 different types of British aircraft and includes, first flight dates, production quantities, mark number variations, dates of service, areas of use, etc.  There are also more than 500 photographs which make this a unique record of all known types of aeroplane of British origin that saw military service during the Second World War.

The book is in very good condition.