Accepted Papers Online
The papers which have already been accepted by the Editors on the basis of the review process, and their contents is fixed and accepted by the Authors, are published online immediately, before the full number is closed. The reason for such policy is to make the accepted publications accessible to the readers as soon as possible.
The accepted papers are already ascribed to the volumes and numbers, and the page numbering is known, so for a paper with this label the full bibliographic data are already fixed and they are given alongside with the title and author(s) information. Therefore, the paper available in this mode can be easily cited. The only difference between the Accepted paper online and the regular paper is that the number it appears in is not closed yet.