The citations Citations (referencing), in which one paper refers to earlier works, are the standard means by which authors acknowledge the source of their methods, ideas and findings, and are often used as a rough measure of a paper's importance. There is an argument of whether citation analysis that is measuring the numbers (count and density) of citations should be considered as a significant influence on what constitutes a classic paper [[16], [29]]. It allows for the relative impact of an article regardless of year of publication; however, although a recently published article may have a high citation density because of its newness it usually takes a few years to acquire classic status [[16]]. These include the types of publications, the time of publication, the size and field of the study, the journal in which the article is published, and the novelty of a subspecialty. [Extracted from the article]