You know the source of the paper by information retrieval, which should be the information obtained from the title database. In fact, the source information in the bibliography is the clue for predecessors to find the original text. People in the past wrote directly to the publishing house to ask for it. Now the network is developed, and many bibliographic databases have made links to get the full text. Please find out if there is a full-text logo on the page. In addition, if it is in Chinese, go to cnki Wanfang and other databases first. For foreign languages, first look at free databases such as pubmed. In fact, pubmed also made a full-text link.