2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/13283A preliminary analysis of fields around 20 mainly radio-quiet QSOs (RQQs) at intermediate redshift is summarized. We find overdensities of faint sources around 50% of our observed QSOs suggesting that they are located in groups or even clusters of galaxies.2 pages (LaTeX, uses paspconf.sty), 2 figures (Postscript). To appear in the Proceedings (PASP conf.ser.) of the "Bl Lac Phenomenon" Conference, held in Turku, 1998 - June 22-26 - ed. Leo TakaloAstrophysicstext