In this chapter, I explore the notion of text segmentation from the viewpoint of discourse analysis. I examine the organization, in the particular context of Chinese medical texts, of the overall discursive tapestry, made up of a range of textual threads, including the author's own discourse and that of others, in the form of citations and quotations. After a first overview on the practice of citation in a corpus made up of twenty-three medical texts produced between the beginning of the eighteenth century and the beginning of the twentieth century, I focus on how the marks of the heterogeneity implied by the overt incorporation of the words, the ideas or the work of others into the flow of a writer's discourse appear in these texts. Paying attention to the syntax and the layout used by writers to interrupt their own discourse and to give the floor to others, I question whether the ways this heterogeneity is made visible can be a clue in distinguishing the different functions citations and quotations meet in Chinese medical literature. I also question whether using one way to cite or another can help in identifying different genres of medical writings at a time when writing in the medical field was not reserved to a professionalized social group.