Letter from Thomas Gold to Donald G Brown, District Director, US Department of Justice, Immigration and Naturalization Service, San Juan, Puerto Rico Telling Mr Brown that they wish to obtain the assistance of Dr Carlos Varsavsky to direct a radio astronomy programme at the Arecibo Ionospheric Observatory. Goes on to tell Mr Brown about the Observatory, the program and Dr Varsavsky. He hopes that a visa can be granted to Dr Varsavsky. 12 December 1967