without SOME reference to the movie.

Follow the yellow brick road

If I only had a brain

There is no place like home.

 I'll get you, my pretty, and your little dog too!

I'm melting!

And you were there, and you, and you

We're not in  Kansas anymore

 Lions, and tigers, and bears! Oh, my!

"man behind the curtain"

All the music...

And so on.

If you include Wicked the musical, the Wiz, etc...