INTER-PERIODIC CORRELATION. 



253 



+ 60 



+ 40 



+ 20 k 



CO 



ao 







PfR/OJJ 770/4 



+ 40 

 + 20 



00 



-20 



PfRIOJ] 70 TO 77 



7 14 21 28 35 42 49 56 63 70 77 



