FIG. 1 is a top, front and right-side perspective view of a refrigerator showing our new design;
FIG. 2 is a bottom, rear and left-side perspective view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a left-side elevation view thereof;
FIG. 6 is a right-side elevation view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is a top, front and right-side perspective view of the refrigerator with the door slightly opened;
FIG. 10 is a front elevation view thereof;
FIG. 11 is a rear elevation view thereof;
FIG. 12 is a left-side elevation view thereof;
FIG. 13 is a right-side elevation view thereof;
FIG. 14 is a top plan view thereof;
FIG. 15 is a bottom plan view thereof;
FIG. 16 is a top, front and right-side perspective view of the refrigerator with the door fully opened;
FIG. 17 is a front elevation view thereof;
FIG. 18 is a rear elevation view thereof;
FIG. 19 is a left-side elevation view thereof;
FIG. 20 is a right-side elevation view thereof;
FIG. 21 is a top plan view thereof; and,
FIG. 22 is a bottom plan view thereof. The broken lines shown in FIGS. 1-22 depict portions of the refrigerator and form no part of the claimed design.