11. The method according to claim 10 , further comprising obtaining the second document data in response to the identifying the second document data.
11. The method according to claim 10 , further comprising obtaining the second document data in response to the identifying the second document data. 12. The method according to claim 11 , wherein the obtaining further includes obtaining third document data corresponding to a second document-specifying character string in the text document data, the second document-specifying character string having no modification relation with the first character string.