We have been looking for this document on the Web. We think we have found the following, freely available version(s) of it: http://cs.engr.uky.edu/~dekhtyar/publications/TODS2001.pshttp://www.cs.umd.edu/%7Edekhtyar/academ/publications/tp-big.pshttp://www.cs.umd.edu/~dekhtyar/academ/publications/tp-final.psFor further information about this item go to:http://portal.acm.org/citation.cfm?id=383734.383736