# NGC 661

> galaxy

**Wikidata**: [Q1038038](https://www.wikidata.org/wiki/Q1038038)  
**Source**: https://4ort.xyz/entity/ngc-661


## References

1. SIMBAD
2. Comparison LEDA/SIMBAD octobre 2002. Catalogue to be published in 2003
3. The Updated Zwicky Catalog (UZC)
4. Gaia Data Release 2
5. The Two Micron All Sky Survey (2MASS)
6. Hunting for supermassive black holes in nearby galaxies with the Hobby-Eberly telescope
7. The ATLAS3D project - I. A volume-limited sample of 260 nearby early-type galaxies: science goals and selection criteria