Near the beginning as the road trip starts, Donovan's Catch the Wind comes on the radio. Stanley Tucci's character, Tusker, says to Colin Firth's character, Sam, "Don't you remember this? Where were you in the 70s?" The song was recorded, released and was in the charts in 1965. Both Stanley and Colin would only have been 4 at the time, although their characters may of course be older.