2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/12793We present recent ROSAT, ASCA and SAX observations of intermediate BL Lac objects (IBLs), i.e. BL Lacs which are located between high-energy and low-energy peaked BL Lac objects with respect to alpha_rx. Both the statistical properties of IBLs from the RGB sample and a detailed broad band X-ray spectral analysis of two objects (1424+2401, 1055+5644) point towards a continuous distribution of synchrotron emission peak frequencies among BL Lac objects.4 pages, 4 figures; to appear in the proceedings of the conference "BL Lac Phenomenon" held in Turku, Finland, June 22-26, 1998Astrophysicstext