| Letter | Year |
|---|---|
| January 1970 – VOL. 51, No. 1 – Head Office: Montreal, January 1970 | January 1970 |
| Vol. 79 N°. 1 – Winter 1998 – The Philosophical Approach | Winter 1998-new |
| December 1969 – VOL. 50, No. 12 – Diplomacy in the Home | December 1969 |
| November 1969 – VOL. 50, No. 11 – Bureaucracy | November 1969 |
| October 1969 – VOL. 50, No. 10 – Hope for the Mentally Retarded | October 1969 |
| September 1969 – VOL. 50, No. 9 – The International Labour Organization | September 1969 |
| August 1969 – VOL. 50, No. 8 – Time to Talk Things Over | August 1969 |
| July 1969 – VOL. 50, No. 7 – In Pursuit of Efficiency | July 1969 |
| June 1969 – VOL. 50, No. 6 – Let Us Enjoy Our Freedoms | June 1969 |
| May 1969 – VOL. 50, No. 5 – Putting Knowledge To Work | May 1969 |