According to the text, who had the idea of guide dogs for blind people ?

Questions 41 and 42

Read the text below to answer questions 41 and 42:

Guide Dogs

During World War I, a doctor at a German hospital was treating a blind patient when a fact called his attention. The doctor left his dog with the patient and when he returned he noticed the positive way that man and dog were interacting. He concluded that such dogs could be trained to assist blind people and started to teach the animals to do just that. Dorothy Eustis, a wealthy American dog trainer, heard of these guide dogs, hired some of the German trainers and opened an institute in New Jersey to make this use of the dogs widespread.
(Fonte:Adapted from http://twotrees.www.50megs.com)