Britvin, Sergey N.
Murashko, Michail N.
Vapnik, Yevgeny
Polekhovsky, Yury S.
Krivovichev, Sergey V.
Article History
Received: 11 November 2014
Accepted: 16 January 2015
First Online: 10 February 2015
Competing interests
: The authors declare no competing financial interests.