Article History
Received: 11 April 2017
Accepted: 12 September 2017
First Online: 15 September 2017
Compliance with ethical standards
:
: Patrizio Petrone, Patricia Jiménez Morillas, Alexander Axelrad, and Corrado P. Marini declare that they have not conflict of interest.
: This research consisted of literature review only, and, therefore, did not involve human participants or animals.