How to judge which author a paper is actually depends on the ranking position of the paper's signature. The first author is the signature of the paper, and so on. The second and third authors are the second and third authors.
Scientific citation index (SCI)
Citation database established by eugene garfield of institute for scientific information (ISI) in Philadelphia on 1957. SCI (Science Citation Index), EI (Engineering Index) and ISTP (Science and Technology Conference Index) are three world-famous retrieval systems for scientific documents, which are internationally recognized as the main retrieval tools for scientific statistics and scientific evaluation.
In February 2020, the Ministry of Education and the Ministry of Science and Technology issued "Several Opinions on Standardizing the Use of Relevant Indicators of SCI Papers in Colleges and Universities and Establishing Correct Evaluation Orientation". This document should break the "SCI supremacy" of papers, take this as a breakthrough, take practical measures with strong pertinence and operability, break the "paper-only theory" and establish a correct evaluation orientation.
The periodicals collected by SCI mainly involve basic scientific research fields such as mathematics, science, chemistry, agriculture, forestry, medicine and biology. The selected journals come from more than 40 countries with more than 50 languages, among which the main countries are the United States, Britain, the Netherlands, Germany, Russia, France, Japan and Canada, and some China (including Hong Kong, Macao and Taiwan) journals are also included.