Jochen Heidt

Exploring Cosmic Evolution with the FORS Deep Field

Ulrich Hopp, Ralf Bender, Klaus J. Fricke, 2004 .

Multiwavelength monitoring of the BL Lacertae object PKS 2155-304. 4: Multiwavelength analysis

A. P. Marscher, Paul S. Smith, G. Tagliaferri, 1995 .

Identification of a complete sample of northern ROSAT All-Sky Survey X-ray sources - II. The optical observations

Wolfgang Voges, F.-J. Zickgraf, Bodo L. Ziegler, 1997 .