Question

What is an example of a reference marker that a source might use?

Answer 1

page numbering is a reference marker that a source might use
page numbering is a process which is used to number the pages of an article or a document

Answer 2

Example of a reference marker that a source might use is "Page numbering".
Page numbering is a process in which it is used to number the pages of the an article or document, It can be a roman numeral or an integer.

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