The arrays of {TAIL ~ permanent magnets} each has {HEAD ~ north and south poles} distributed in both longitudinal and latitudinal directions along a plane 
The arrays of { TAIL ~ permanent magnets } each has { HEAD ~ north and south poles } distributed in both longitudinal and latitudinal directions along a plane
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH