15. The information processing method according to claim 14 , further comprising visiting reference targets designated by reference information included in the plurality of the texts to detect that the same information being reached by using two or more pieces of reference information; and replacing the two or more pieces of reference information with the same character string in response to an output from the reference detection unit.
14. An information processing method comprising: detecting, by a detection unit having a matching unit for determining that a character string included in a text is a quotation from a reference target when the character string is included in information obtained by accessing the reference target designated by reference target information included in the text, from a plurality of texts, quotations from other texts; deleting or replacing with predetermined character strings the quotations in a plurality of the texts in a memory; executing text mining for a plurality of the converted texts by calculating the degree of similarity between information available from reference targets associated with different quotations of different contents, and grouping the quotations based on the degree of similarity; and replacing reference target information with regular reference target information when reference target information indicating a regular reference target is included in information obtained by accessing the reference target designated by the reference target information.