5 Sources about my topic

XochimilcO

Wikipedia: The Free Enccyclopedia

http://en.wikipedia.org/wiki/Xochimilco

Planeta.com

http://www.planeta.com/ecotravel/mexico/df/xochimilco.html

Wikitravel

http://wikitravel.org/en/Mexico_City/Xochimilco

UNESCO

http://whc.unesco.org/en/list/412

BBC Learning English Blog

http://www.bbc.co.uk/blogs/learningenglish/2010/05/xochimilco-trajineras-mariachi.shtml