Petäjä, T.
Järvi, L.
Kerminen, V.-M.
Ding, A.J.
Sun, J.N.
Nie, W.
Kujansuu, J.
Virkkula, A.
Yang, X.
Fu, C.B.
Zilitinkevich, S.
Kulmala, M.
Article History
Received: 24 July 2015
Accepted: 6 November 2015
First Online: 12 January 2016
Competing interests
: The authors declare no competing financial interests.