Asongu, Simplice A.
Nnanna, Joseph
Acha-Anyi, Paul N.
Article History
Received: 30 October 2019
Revised: 2 January 2020
Accepted: 18 January 2020
First Online: 1 February 2020
Ethics approval and consent to participate
: This article does not contain any studies with human participants or animals performed by the authors.
: Not applicable.
: The authors declare that they have no competing interests.