Vaiana G.S., G. Fabbiano, R. Giacconi, L. Golub, P. Gorenstein, F.R. Harnden Jr., J.P. Cassinelli, B.M. Haisch, H.M. Johnson, J.L. Linsky, and C.W. Maxson, The Astrophysical Journal 245, 163-182 (1981).
a joint institute of 
and 
and