Overview
Genre
| Fairies | 1 | Overview | Omit | Problems |
| Retro | 1 | Overview | Omit | Problems |
Authors
| Heinonen, Unto | 2 | Overview | Omit | Problems |
Sources
| Problemkiste | 2 | Overview | Omit | Problems |
| Phenix | 1 | Overview | Omit | Problems |
Keywords
| Vier Ecken | 2 | Overview | Omit | Problems |
| Circe | 1 | Overview | Omit | Problems |
| Eindeutige Beweispartie | 1 | Overview | Omit | Problems |
| Madrasi | 1 | Overview | Omit | Problems |
| Reiner Rundlauf | 1 | Overview | Omit | Problems |
| Serienzüger | 1 | Overview | Omit | Problems |
Pieces
| Grashüpfer | 1 | Overview | Omit | Problems |
Computer tested
| C+ | 2 | Overview | Omit | Problems |
Cooked
| not cooked | 2 | Overview | Omit | Problems |
https://pdb.dieschwalbe.de/overview.jsp?expression=A%3D%27Heinonen%27+AND+K%3D%27Vier+Ecken%27