The phenomenon of frogs falling from the sky during severe storms is a well-documented meteorological and zoological oddity caused by strong updrafts or waterspouts sweeping up small animals, requiring no further citation.
The claim describes a well-known natural phenomenon (animal rain) that, while unusual, is common knowledge and a recognized meteorological event, though none of the retrieved papers discuss zoological precipitation (they focus on weather radar, rain-on-snow events, air pollution, wind turbines, etc.). Thus, it is classified as common knowledge with no papers attached.