The multiple print engine 7, wherein {HEAD ~ the raster image processor} comprises {TAIL ~ a single raster image processor} 
comprises
The multiple print engine 7 , wherein { HEAD ~ the raster image processor } comprises { TAIL ~ a single raster image processor }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL