DEMANDS ON LASER PURITY IN AN INTERFEROMETRIC GRAVITATIONAL WAVE DETECTOR A. Rüdiger, R. Schilling, L. Schnupp, W. Winkler, H. Billing and K. Maischberger J. Phys. Colloques, 42 C8 (1981) C8-451-C8-459 DOI: 10.1051/jphyscol:1981851