{TAIL ~ Optimal alignments} in {HEAD ~ linear space}, CABIOS 4:1, 11 17; Chao, K M, W. R. Pearson and W. Miller 
{ TAIL ~ Optimal alignments } in { HEAD ~ linear space } , CABIOS 4:1 , 11 17 ; Chao , K M , W. R. Pearson and W. Miller
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH