| Number | Name | Date | Kind |
|---|---|---|---|
| 1616743 | Ericsson | Feb 1927 | |
| 3747896 | Warren | Jul 1973 | |
| 3867997 | Hyslop, Jr. | Feb 1975 | |
| 4236698 | Compte | Dec 1980 | |
| 4276959 | Barber | Jul 1981 | |
| 4598794 | Anderson | Jul 1986 | |
| 4641728 | McCabe | Feb 1987 | |
| 4666131 | Kettelkamp | May 1987 | |
| 4673060 | Gregory | Jun 1987 | |
| 5307899 | Lubinski | May 1994 | |
| 5314167 | Holloman | May 1994 | |
| 5638917 | Vennen | Jun 1997 |
| Number | Date | Country |
|---|---|---|
| 814167 | Jun 1969 | CAX |
| 1507714 | Dec 1967 | FRX |
| 414126 | Dec 1966 | CHX |
| 1579240 | Nov 1980 | GBX |
| Entry |
|---|
| Aberdeen's Magazine of Masonry Construction, Oct. 1996, vol. 9, No. 10, p. 455. |
| Alum-A-Pole Corporation 1985 Brochure (2 pages). |