EN 
| Letter | Year |
|---|---|
| April 1969 – VOL. 50, No. 4 – To Be Young Today | April 1969 |
| March 1969 – VOL. 50, No. 3 – Respect for the Law | March 1969 |
| February 1969 – VOL. 50, No. 2 – Man in the Balance of Nature | February 1969 |
| January 1969 – VOL. 50, No. 1 – The Golden Age of Child Health | January 1969 |
| December 1968 – VOL. 49, No. 12 – On Thinking Things Through | December 1968 |
| November 1968 – VOL. 49, No. 11 – About Reducing Friction | November 1968 |
| October 1968 – VOL. 49, No. 10 – What Use is Advertising? | October 1968 |
| September 1968 – VOL. 49, No. 9 – Misuse of Drugs.” Some Facts | September 1968 |
| August 1968 – VOL. 49, No. 8 – This Matter of Judgment | August 1968 |
| July 1968 – VOL. 49, No. 7 – A Business Man’s Qualities | July 1968 |