Bibliography

'Birka'. __Wikipedia.__ 21 June- 2011. []

'Birka and Hovgarden'. __Unesco.__ 30 June 2011. []

'Birka: Trade Center and Gateway for of Viking age Sweden'. __Viking Answer Lady.__ 4 July 2011. [|http://www.vikinganswerlady.com/Birka.shtml]

Thanks to GO!Animate for the animation