You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "when was free movement in the eu introduced?" whose answer is 1957.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when was free movement in the eu introduced
Useful Output:

Doc 1: These freedoms were enshrined in 1957 in the Treaty of Rome, which established the EU's predecessor, the European Economic Community (EEC).
Doc 2: The concept of free movement was established with the creation of the European Economic Community (EEC) in 1957, which later evolved into the
Doc 3: The right to free movement finally reached its pinnacle of applying to all Member State nationals in 1992, with the signing of the Maastricht
Doc 4: The Messina Conference in June 1955 took the realisation of free movement one stage further: the Member States of the ECSC resolved to set up a
Doc 5: The EU was established, along with its citizenship, when the Maastricht Treaty came into force in 1993, and was incorporated as an international legal juridical