A processor selects {HEAD ~ pages} from the page buffer and outputs them to select ones of a plurality of {TAIL ~ printers} in a predetermined order 
A processor selects { HEAD ~ pages } from the page buffer and outputs them to select ones of a plurality of { TAIL ~ printers } in a predetermined order
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH