The ornamental design for a cover, as shown and described.
FIG. 1 is a front view of a cover showing our new design.
FIG. 2 is a rear view thereof.
FIG. 3 is a top plan view thereof.
FIG. 4 is a bottom view thereof.
FIG. 5 is a left side view thereof.
FIG. 6 is a right side view thereof.
FIG. 7 is a front view thereof showing the position of line 8-8.
FIG. 8 is an enlarged cross-sectional view thereof, taken along line 8-8 in FIG. 7.
FIG. 9 is a front perspective thereof, shown in a position of use. The broken lines showing a book, pen, paper, headphones and rectangular device form no part of the claim; and,
FIG. 10 is a rear perspective thereof, shown in a position of use with inner leaves.
The applicant claims protection for the parts indicated by continuous lines.