%0 Journal Article %A Paul, Annegret %T First Occurrence for the Dual Pairs (U(p, q), U(r, s)) %J Canadian journal of mathematics %D 1999 %P 636-657 %V 51 %N 3 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1999-029-6/ %R 10.4153/CJM-1999-029-6 %F 10_4153_CJM_1999_029_6