An X-ray Map of the W44 Supernova Remnant from the EINSTEIN Observatory. Rolf, D. ; Harnden, F. R. ; Gorenstein, P. ; Pye, J. P. ; Seward, F. D. ; Willingale, R. Abstract Publication: Bulletin of the American Astronomical Society Pub Date: September 1979 Bibcode: 1979BAAS...11..796R