== References ==*ETag in HTTP/1.1 specification*Concerning Etags and Datestamps by Lars R. Clausen (2004)==External links==*Apache HTTP Server Documentation – FileETag Directive*"Editing the Web: Detecting the Lost Update Problem Using Unreserved Checkout," W3C Note, 10 May 1999.
* ETag in HTTP/1.1 specification* Concerning Etags and Datestamps by Lars R. Clausen (2004)== Внешние ссылки ==* Apache HTTP Server Documentation - FileETag Directive* "Editing the Web: Detecting the Lost Update Problem Using Unreserved Checkout," W3C Note, 10 May 1999.