@article {PS20, title = {The $\varepsilon-\varepsilon^β$ property in the isoperimetric problem with double density, and the regularity of isoperimetric sets}, journal = {Adv. Nonlinear Stud.}, volume = {20}, number = {3}, year = {2020}, pages = {539{\textendash}555}, doi = {10.1515/ans-2020-2074}, author = {Pratelli, A. and Saracco, G.} }