X-ray and Near-infrared Studies of a Star-forming Cloud; L1448

X-ray and Near-IR Variability of the Anomalous X-ray Pulsar 1E 1048.1-5937: From Quiescence Back to Activity

X-ray and optical analysis of Abell 85.

X-ray and optical bursts and flares in YSOs: results from a 5-day XMM-Newton monitoring campaign of L1551

X-ray and optical counterparts of hard X-ray selected sources from the SHEEP survey: first results

X-ray and optical coverage of 3EG J0616-3310 and 3EG J1249-8330

X-ray and Optical Eclipses in ULXs as Possible Indicators of Black Hole Mass

X-ray and optical emission-line filaments in the cooling flow cluster 2A 0335 + 096

X-ray and Optical Filaments in M87

X-Ray And Optical Flux Ratio Anomalies In Quadruply Lensed Quasars. II. Mapping the Dark Matter Content in Elliptical Galaxies

X-Ray and Optical Flux Ratio Anomalies in Quadruply Lensed Quasars: I. Zooming in on Quasar Emission Regions

X-ray and optical follow-up observations of the August 1998 X-ray transient in NGC6440

X-ray and optical followup of gamma-ray (up to TeV) sources

X-Ray and Optical Microlensing in the Lensed Quasar PG 1115+080

X-ray and Optical Monitoring of the Peculiar Source 4U 1700+24/HD154791

X-ray and optical monitoring of the peculiar source 4U 1700+24/V934 Her

X-ray and optical observations of 1RXS J154814.5-452845: a new intermediate polar with soft X-ray emission

X-ray and optical observations of 2 new cataclysmic variables.

X-Ray and Optical Observations of A 0535+26

X-ray and optical observations of a new ROSAT discovered polar: RX J0453.4-4213.