摘要：

A process which provides a three-dimensional, light-diffracting pattern comprising a hologram on a surface of a transparent material layer which may be extremely thin and non-self-supporting, and which secures this layer to a document or like substrate, with the pattern-bearing surface facing downwardly (i.e., not exposed), by an adhesive bond having a shear strength greater than that of the transparent layer so that the layer cannot be removed from the surface without being destroyed.

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