Kawada, Tomoyuki http://orcid.org/0000-0002-4426-4644
Article History
Received: 13 December 2019
Accepted: 1 January 2020
First Online: 6 February 2020
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human or animal subjects performed by the any of the authors.
: For this type of study, formal consent is not required.
Free to read: This content has been made available to all.