1. Protoceratops Andrewsi
   Information, facts and several skeletal pictures of these dinosaurs.
   http: //mathematical.com/dinoprotoceratops.html...
   
   
2. Encyclopędia Britannica - Protoceratops
   An Encyclopedia Britannica article on Protoceratops
   http: //britannica.com/bcom/eb/article/9/0,5716...