An outer portion or tab of {HEAD ~ each folded partition} is secured to one of {TAIL ~ the other partitions} to prevent disassembly of the matrix 
An outer portion or tab of { HEAD ~ each folded partition } is secured to one of { TAIL ~ the other partitions } to prevent disassembly of the matrix
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH