| http://www.w3.org/ns/prov#value | - I It is found that during the bending or creasing operations cracks occur in the board due to the fact that many kinds of cardboard, fiberboard or the like are so constituted as not to allow of any local expansion or contraction of the fibers in the working area under the influence of the tools, this being particularly noticeable when the materials are subjected to the action of the tools across t
|
