THE THREE SONG by Mason Williams (http://www.masonwilliams-online.com) is a song in which three people each sing three songs but the three songs they each sing build into the other songs – essentially it's one song that's nine songs but built upon combination of three songs into one song.  I suppose one could call it a song of nines, a nine song, or the three threes song.  Confused?  Well, who better to provide an example of this musical form than the Smothers Brothers (http://www.smothersbrothers.com) who refer to it as "sort of like a classical fugue" which is a form of contrapuntal composition while I just think it's very pretty.  In a clip from their Smothers Brothers Comedy Hour, 9 April 1967, The Three Song is explained and performed by Tommy Smothers, Dickie Smothers, and Ester Ofarim (http://www.esther-ofarim.de).

The lyrics to the song are as follows so you can follow along:

Little winds sing a song of the sun in the sky
and I know, like the wind, the songs will always be there.

In your hair, soft and warm, light of dawn, shining fair,
in your voice, as you sing, the songs will always be there.

Little winds (in your hair) sing a song (soft and warm) of the sun (light of dawn) in the sky (shining fair)
And I know (in your voice), like the wind (as you sing), the songs will always be there.

Little wines are the kiss of the fruit from the earth and I know, there I taste surely the sweetest of all.
In your lips, sweet as dew, on the vine in the fall.
The first kiss from your lips is surely the sweetest of all.

Little wines (in your lips) are the kiss (sweet as dew) of the fruit (on the vine) from the earth (in the fall)
And I know (the first kiss) there I taste (from your lips) is surely the sweetest of all.

Little stars (in your eyes) twinkle bright (like the sky) in the still (of the night) sky above (it is true)
And I know (that I love) only you (only you) wish it so to be true.

lalalala….

The songs will always be there!

While not the best known of the songs from the show, this one's very delightful.