Convertible Bookcase

FIG. 1 is a front perspective view of a convertible bookcase showing the new design;

FIG. 2 is a left side view, the right side view being a mirror thereof;

FIG. 3 is a front view, the rear view being a mirror thereof;

FIG. 4 is a top view; and,

FIG. 5 is a bottom view.

The broken lines shown in the drawings are for the purpose of illustrating portions of the article and form no part of the claimed design.

The surface shading is intended to depict surface contour and forms no part of the claimed design.