Abstract: Reproduction apparatus for producing duplex collated copies from duplex and simplex original documents. A document feeding section circulates original document sheets a plurality of times to an exposure position. In a duplex mode of operation, the originals are inverted between alternative odd and even circulations such that even pages are presented for exposure on the first and every subsequent odd circulation and odd pages are presented for exposure on the second and every subsequent even circulation. In a simplex mode of operation, the pages are copied selectively, even pages on odd circulations, and the odd pages on even circulations. A duplexing section of the copier, including a first-in first-out intermediate hopper, operates in coordination with the feeding section to present and re-present copy supports to a position for receiving images on the appropriate first and second faces of the copy supports.