"ORM 2"(PDF). Archived from the original(PDF) on February 19, 2009. Retrieved April 22, 2009. Halpin, T. 2005, 'ORM 2', On the Move to Meaningful Internet Systems 2005: OTM 2005 Workshops, eds R. Meersman, Z. Tari, P. Herrero et al., Cyprus. Springer LNCS 3762, pp. 676–87.
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web.archive.org
"ORM 2"(PDF). Archived from the original(PDF) on February 19, 2009. Retrieved April 22, 2009. Halpin, T. 2005, 'ORM 2', On the Move to Meaningful Internet Systems 2005: OTM 2005 Workshops, eds R. Meersman, Z. Tari, P. Herrero et al., Cyprus. Springer LNCS 3762, pp. 676–87.