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