Correct spelling of a media expression in Less?

Question

css

Can you please tell me which of the media expressions is written correctly (the difference is in quotes) and how can I check if the media expression works when loading images? I know that there are retina device emulators in the console, but if the media expression fails, browsers connect a regular image.
@retina: ~"(min-resolution: 144dpi)", ~"(min-resolution: 1.5dppx)";
@retina: ~"(min-resolution: 144dpi)", "(min-resolution: 1.5dppx)";
@retina: ~"(min-resolution: 144dpi), (min-resolution: 1.5dppx)";