A license is an official and legal document that is issued by competent authorities in order to carry out a specific activity. It is obvious that for each subject of activity, a license must be obtained from the legal authorities related to that subject of activity. In other words, if obtaining a license for any business must be done from authorities that are related to the subject of that business and activity. For example, in order to carry out cultural and artistic affairs, it is necessary to obtain permission from institutions related to culture and art, or in technical, industrial or agricultural activities, it is necessary to obtain permission from related ministries. Now, if the specialists and experts of these fields refer to these authorities and courts as attorneys and proxies to obtain legal permits, while speeding up the affairs, the purposes of the reference will be achieved in the best way.