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The narrow strip of a piece of sheet material that is created when the sheet material is folded along the spine edge, making one wide leaf on one side of the fold and one narrow strip, or stub, on the other. Hook endleaves and outside hook endleaves are both folded to create stubs, as are guards. In the latter case, both elements are stubs, though the outer element is usually wider than the inner (it may be up to half the width of the text leaves, beyond which it should be described as a leaf). Many single leaves, most often plates in the form of maps or illustrations, will also be folded around text gatherings with a stub on the other side of the fold.

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