@conference {Chiaramella_90:A,
	title = {A retrieval model based on an extended modal logic and its application to RIME experimental approach},
	booktitle = {13th ACM-SIGIR, Bruxelles,},
	year = {1990},
	pages = {25-43},
	author = {Y. Chiaramella and Jian-Yun Nie}
}
