Ulikowski, D. (2004) European catfish (Silurus glanis L.) reproduction outside of the spawning season. Archives of Polish Fisheries/Archiwum Rybactwa Polskiego [Arch. Pol. Fish./Arch. Ryb. Pol.], pp. 121-131
| Species | Development state | Trait | Primary Data | Secondary Data |
| Silurus glanis | Spawning conditions | Spawning season | June, thermophilic species | ['June'] |
| Silurus glanis | Spawning conditions | Spawning temperature | Exceed 18 | 18.0 °C |