@article {4002,
	title = {Saving Space and Time Using Index Merging},
	journal = {Data \& Knowledge Engineering (DKE)},
	volume = {69},
	year = {2010},
	pages = {1062--1080},
	doi = {10.1016/j.datak.2010.07.011},
	author = {Lubomir Stanchev and Grant Weddell}
}
