The Complexity of Existential Quantification in Concept Languages

@techreport{pub5997,
    author = {

Donini, Francesco
 and 

Hollunder, Bernhard
 and 

Lenzerini, Maurizio
 and 

Spaccamela, Alberto Marchetti
 and 

Nardi, Daniele
 and 

Nutt, Werner
},
    title = {The Complexity of Existential Quantification in Concept Languages},
    series = {DFKI Research Reports (RR)},
    year = {1991},
    volume = {91-02},
    pages = {22},
    institution = {DFKI}
}