| Number | Date | Country | Kind |
|---|---|---|---|
| 2711826 | Mar 1977 | DEX | |
| 2740374 | Sep 1977 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2813312 | Loue et al. | Nov 1957 | |
| 3052930 | Mathews | Sep 1962 | |
| 3281993 | Riegelman | Nov 1966 | |
| 3384998 | Abramson | May 1968 | |
| 3942197 | Sudmann et al. | Mar 1976 | |
| 4014070 | Rifkin | Mar 1977 | |
| 4073035 | Baus | Feb 1978 |
| Number | Date | Country |
|---|---|---|
| 2634744 | Dec 1977 | DEX |
| 617407 | Feb 1949 | GBX |
| Entry |
|---|
| "Sliding Steel Sash", The Architectural Forum, p. 210, Mar. 1939. |