What's the song thay plays in episode 13 when Eren takes a big rock to the hole in wall?

Question

There's a song in Attack on Titan season 1 episode 13 at about 13:00 when Eren takes a big rock to the hole in the wall.

What's the name of the song, and where can I legally buy or listen to this song?

Answer 1

The song title is "Call Your Name" (track #15) with vocals by mpi & CASG.

You can buy the Audio CD at Amazon and it has the full OST of Attack on Titan.