@article {PS18,
	title = {On the isoperimetric problem with double density},
	journal = {Nonlinear Anal.},
	volume = {177},
	number = {Part B},
	year = {2018},
	pages = {733{\textendash}752},
	doi = {10.1016/j.na.2018.04.009},
	author = {Pratelli, A. and Saracco, G.}
}
