Frank Nack Jacco van Ossenbruggen Lynda Hardman That Obscure Object of Desire: Multimedia Metadata on the Web, Part 2. 54-63 2005 12 IEEE MultiMedia 1 http://doi.ieeecomputersociety.org/10.1109/MMUL.2005.12 db/journals/ieeemm/ieeemm12.html#NackOH05