Life / "Hej Sokoly" - song research [11]

hey I'm looking for as much possible information on this song as possible, I'm doing a project for a music theory class of mine, ill be doing a variation on it and my choir will eventually sing it, so i need as much information on this as possible!

smbit11.republika.pl/music/sokoly.htm

i found this, but im not sure how accurate it is, ive found a few versions of it.

some things im looking for:
the history of the song
accurate sheet music
good CD's of this song and others like it.
+ anything else you can add.

thanks everyone!