Zodiac Cipher – The Monster of Florence – Addressed envelope of his letter sent to Monica Silvia – Secretary General of NATO – (Unnumbered)
The 5th Secretary-General of NATO from October 1, 1971 to June 25, 1984 was, the Dutchman, Joseph Luns.
Note, that the first 4 Secretary-Generals of NATO had all died of old age by the year 1980.