http://www.cografya.org/nufus-piramitleri-ve-ozellikleri.html
bide vidyo :
https://www.google.com.tr/search?q=10.+s%C4%B1n%C4%B1f+co%C4%9Frafya+n%C3%BCfus+piramitleri+konu+anlat%C4%B1m%C4%B1&hl=tr&newwindow=1&tbo=d&source=lnms&tbm=vid&sa=X&ei=MjT3UKGlHail4ASb4YCwAw&ved=0CAsQ_AUoAA&biw=1366&bih=643
