Assembly not found

Aug 12, 2014 at 11:45 AM
Helix 3D Toolkit library I downloaded and tried to use it in my project but I get this error.

"Assembly HelixToolkit.Wpf was not found"

"Assembly HelixToolkit.Wpf.Input was not found"

This is code xaml:
I put a picture to see that I added the anssembly