Ferguson said: "We had a pivotal moment a few years ago when my players surrounded Andy D'Urso.
"I was off my head with them, I thought it was ridiculous. It never happened again.
"We tell them to shake the hand of the referee after the game, when it is finished.
"It is sometimes difficult but you have to do it, in the same way as when you lose a game and you invite the opposing manager in for a drink after the game.
"I saw the other night one of my players changed his jersey with one of the Bolton players who had committed 10 fouls against him.
"I said that was good because the match was over, all forgotten, we move on with life. I think that's what we have to do.
"We are talking about introducing this into the grass-roots level, respect for the referee. It is absolutely correct.
"The haranguing of referees is ridiculous, we know that."