https://ntrs.nasa.gov/citations/19930009940
Observations of OH in comet Levy with the Nancay radio telescope - NASA Technical Reports Server...
Due to extremely favorable excitation conditions, comet Levy (1990c) exhibited in August-September 1990 the strongest OH 18-cm signal ever recorded in a comet...
nancay radio telescopecomet levywith theobservationsnasa