Defending the Realm - MI5 and the Shayler Affair - Mark Hollingsworth and Nick Fielding

UK Eyes Alpha - Mark Urban

The Enemy Within. The Secret War Against the Miners - Seumas Milne

The Miners' Strike - Geoffrey Goodman

Smear! Wilson and the Secret State - Stephen Dorril and Robin Ramsay

In Defence of the Realm? - Richard Norton-Taylor

Spycatcher - Peter Wright

On Her Majesty's Secret Service - Christopher Andrew

The Wilson Plot - David Leigh

The Pencourt File - Barrie Penrose and Roger de Courtiour

Their Trade is Treachery - Chapman Pincher

Harold Wilson - Ben Pimlott

The Silent Conspiracy - Stephen Dorril (Inside the intelligence services in the 1990s)

Enemy Within - Rise and Fall of British Communist Party - Francis Beckett

Free Agent - The Unseen War 1941-91 - Brian Crozier

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Official Secrets Act 1989

The Security Service Act

MI5 The Security Service (HMSO)

Metropolitan Police Special Branch

Liberty