Oce CS520 User Manual page 75

Positioning Originals
When selecting Dual Page, Non-Image Area Erase, AUTO mode in Repeat, or
AUTO Layout, DO NOT CLOSE the document feeder. For details on each
function, see Section 11: "Applications".
Do not place too heavy originals, or do not press strongly when thick
original is placed and is under pressure of RADF; otherwise the
glass may be broken and you may be injured.
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