Shelf

FIG. 1 is a front, right, top perspective view of the shelf, showing my new design;

FIG. 2 is a rear, left, bottom perspective view thereof;

FIG. 3 is a front, left, bottom perspective view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is a right side view thereof;

FIG. 8 is a top plan view thereof; and,

FIG. 9 is a bottom plan view thereof.

The dashed broken lines in the figures are for the purposes of illustrating portions of the shelf and form no part of the claimed design.