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		| Paper: | A deep ROSAT survey |  
		| Volume: | 21, The Space Distribution of Quasars |  
		| Page: | 6 |  
		| Authors: | Georgantopoulos, I.; Stewart, G. C.; Pounds, K. A.; Shanks, T.; Boyle, B. J.; Griffiths, R. E. |  
		| Abstract: | We discuss results from a deep ROSAT observation of a high galactic latitude field. The aim is to resolve directly the major constituents of the X-ray background. We detect a high surface density of X-ray sources (greater than 100/sq deg). Spectroscopic follow up observations have shown that the majority of these sources are QSOs with a surface density of 69 +/- 14/sq deg. The identified QSOs contribute 30 percent of the 1 keV X-ray background. |  
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