The Des Moines Register
| November 23, 1975 |
| December 3, 1975 |
| March 30, 1980 |
| April 30, 1980 |
| May 1, 1980 |
| January 19, 1982 |
| December 8, 1983 |
| February 19, 1991 |
| January 2, 1994 |
| February 12, 1994 |
| April 22, 2001 |
| April 28, 2001 |
| June 12, 2001 |
| December 14, 2002 |
| May 16, 2003 |
| April 29, 2004 |
| April 5, 2009 |
| April 19, 2015 |