@book{21983,
	author = {Choudhary, Debi, ed. and Strassmeier, Klaus, ed.},
	title = {The Physics of Sun and Star Spots},
	publisher = {Cambridge University Press                                  },
	year = {2011},
	series = {IAU Symposium; no. 273},
	address = {Cambridge                                                   },
	url = {https://www.cambridge.org/core/journals/proceedings-of-the-international-astronomical-union/issue/F8F75B893B30EE588DCFD45EDEC53A86}
}