Giampio Bracchi, Domenico Ferrari, Marco Somalvico. A Multilevel Data Structure for Complex Hierarchies of Interrelated Data. In Record of the 1970 ACM SIGFIDET Workshop on Data Description and Access, November 15-16, 1970, Rice University, Houston, Texas, USA (Second Edition with an Appendix). pages 246-275, ACM, 1970. [doi]
Abstract is missing.