@inproceedings{SAC-2002-FerriPR,
	author        = "Fernando Ferri and Elaheh Pourabbas and Maurizio Rafanelli",
	booktitle     = "{Proceedings of the 17th Symposium on Applied Computing}",
	doi           = "10.1145/508791.508873",
	pages         = "432--437",
	publisher     = "{ACM}",
	title         = "{The syntactic and semantic correctness of pictorial configurations to query geographic databases by PQL}",
	year          = 2002,
}