%0 Journal Article
%A Casselman, W.
%T The unramified principal series of $p$-adic groups. I. The spherical function
%J Compositio Mathematica
%D 1980
%P 387-406
%V 40
%N 3
%I Sijthoff et Noordhoff International Publishers
%U http://archive.numdam.org/item/CM_1980__40_3_387_0/
%G en
%F CM_1980__40_3_387_0