As stated the credit for authorship will be awarded to whom will meet following four criteria. 

a. Substantial contribution to conception or design of the work; or the acquisition, analysis, or interpretation of data for the work 
b. Drafting of the work or revising it critically for important intellectual content 
c. Final approval of the version to be published 
d. Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved 

It is the collectively responsibility of authors to determine that all people named as authors meet all four criteria. The named corresponding Author will be responsible for all communication with the editor’s office during the submission, review and publication process.

There is no restriction on number of authors. However any change in the order of authors, removal or addition of author after submission will be done only after a signed statement of agreement for the requested change from all listed authors and from the author to be removed or added is received by Editor-in-Chief.

Any person who has contributed but does not fulfill all 4 criteria of authorship should acknowledged and not listed as authors.