APA (7th ed.) Citation

Great Britain. Foreign Office & Great Britain. Public Record Office. Political Departments, general correspondence from 1906-1966. Public Record Office.

Chicago Style (17th ed.) Citation

Great Britain. Foreign Office and Great Britain. Public Record Office. Political Departments, General Correspondence from 1906-1966. London: Public Record Office.

MLA (8th ed.) Citation

Great Britain. Foreign Office and Great Britain. Public Record Office. Political Departments, General Correspondence from 1906-1966. Public Record Office.