บรรณานุกรม

https://sites.google.com/site/dxkthiwli/prawati-khwam-pen-ma-khxng-dxk-thiw-lip


http://my.dek-d.com/kurama1412/blog/?blog_id=10045821%20%20%A4%C7%D2%C1%CB%C1%D2%C2


http://travel.mthai.com/world-travel/46634.html



http://www.meetawee.com/home/travel-info/season-tour/tulip-netherland.html

http://www.wanthai.com/howto/how-to-tulip