https://www.aanda.org/articles/aa/full_html/2025/07/aa55235-25/aa55235-25.html
Origin of the ring ellipticity in the black hole images of M87* | Astronomy & Astrophysics (A&A)
https://www.usgs.gov/publications/rayleigh-wave-ellipticity-weakly-heterogeneous-layered-media
Rayleigh-wave ellipticity in weakly heterogeneous layered media | U.S. Geological Survey
We derive approximate expressions for the ellipticity (i.e. horizontal-to-vertical or vertical-to-horizontal ratio) of Rayleigh waves propagating in a layered...
rayleigh wave
https://arxiv.org/abs/1403.1440
[1403.1440] Positive curvature and rational ellipticity
Abstract page for arXiv paper 1403.1440: Positive curvature and rational ellipticity
positive curvature14031440rationalellipticity