In SCI, the order of * * * and correspondence authors is similar to the position of paper authors, that is, those who have made significant contributions rank first, and then second. Because even * * * communicates with the author, there must be a distinction between the front and back positions, so the communication author ranked first is absolutely recognized.

Of course, in addition, the author can also mark the names of two correspondents in the upper right corner of the manuscript, and then explain this mark in the footnote on the first page of the article ("××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××××

As long as it is explained, there is no special requirement, but for China, there should be no * * * correspondent at present, and there should be * * * with the first author. * * * It is common for foreign countries to have the same correspondent, because foreign countries value the correspondent more, while China is the first author.