| Keyword(s) | Country | Catalog Listed? | |
| I POLSKA WYSTAWA MAREK (overprint) | Poland, semipostals [White Cross Society]. | Real |  |
| POCZTA POLSKA (overprint on German occupation stamps) | Poland. | Real |  |
| POCZTA POLSKA (overprint on stamps of Austria) | Poland (1918). | Real |  |
| POCZTA POLSKA (overprint on stamps of Germany) | Poland Poznan issues (1919). | Real |  |
| POLSKA | Poland. | Real |  |
| FEN | (currency overprint with Poczta Polska) Poland (1918) [Fenigy]. | Real |  |