They called here. I found helpful information on Amazon to block all calls. They call once and I can choose to block them. It is real techniques that makes sure they do not call twice. I found it here: :

http://www.amazon.com/Who-Called-Me-Number-Collection/dp/1469997819/ref=sr_1_50?s=books&ie=UTF8&qid=1371489451&sr=1-50&keywords=who+called+me