Liz46, you are incorrect- no one voted to 'go into Europe'.
For a start Europe is a continent that, baring some sort of massive earthquake that sends our landmass westwards, the UK will always be part of! Secondly, no one voted to join the Common Market, as it was then. Mr Heath signed for the UK to join in 1973 without a vote, and in 1973 Mr Wilson gave the country a referendum on whether the UK should withdraw.
The vote was to stay after a campaign ( surprise, surprise) of doom and gloom if we were to leave. In those days, you are correct though, the winning vote was seen to be enacted upon without doubt. Not so today, it seems.