- What is the dart frog toxin allegedly used to kill Alexei Navalny? BBC
- Russian opposition leader Alexei Navalny was poisoned by deadly ‘dart frog’ toxin, Europeans say NBC News
- Russian opposition figure Navalny killed by toxin found in poison dart frogs, Europeans say CNN
- Rubio says US does not dispute Navalny poisoning assessment by Europeans Reuters
- Navalny Was Poisoned With Frog Toxin, European Governments Say The New York Times
