db/conf/gis/TzouramanisVM98.html Theodoros Tzouramanis Michael Vassilakopoulos Yannis Manolopoulos Overlapping Linear Quadtrees: A Spatio-Temporal Access Method. 1-7 GIS1998/P001.pdf 1998 conf/gis/98 ACM-GIS http://doi.acm.org/10.1145/288692.288695 db/conf/gis/gis98.html#TzouramanisVM98