The spectrum of the cosmic X-ray background observed by RTXE/PCA M. Revnivtsev, M. Gilfanov, R. Sunyaev, K. Jahoda and C. Markwardt A&A, 411 3 (2003) 329-334 Published online: 17 November 2003 DOI: 10.1051/0004-6361:20031386