# Messier 81

> galaxy in the constellation Ursa Major

**Wikidata**: [Q81102410](https://www.wikidata.org/wiki/Q81102410)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Messier_81)  
**Source**: https://4ort.xyz/entity/messier-81


## References

1. SIMBAD
2. [Messier 81](http://www.messier.seds.org/m/m081.html)
3. The systematics of galaxy morphology in the comprehensive de Vaucouleurs revised Hubble-Sandage classification system: application to the EFIGI sample
4. [Source](https://github.com/JohnMarkOckerbloom/ftl/blob/master/data/wikimap)
5. Library of Congress
6. [Source](http://haroldcorwin.net/rc3/rc39b.csv.gz)
7. Freebase Data Dumps. 2013
8. The complete census of optically selected AGNs in the Coma supercluster: the dependence of AGN activity on the local environment
9. The GALEX Ultraviolet Atlas of Nearby Galaxies
10. The Two Micron All Sky Survey (2MASS)
11. The SDSS Photometric Catalog, Release 7
12. The seventh data release of the Sloan Digital Sky Survey
13. Gaia Early Data Release 3
14. Cosmicflows-3
15. Galaxy groups: a 2MASS catalog
16. The Local Tully-Fisher relation for dwarf galaxies
17. Morphological properties of galaxies in different Local Volume environments
18. The second realization of the international celestial reference frame by very long baseline interferometry
19. National Library of Israel