TY JOUR TI Asymptotics of Far Fields of Surface and Internal Gravitational Waves from Local and Nonlocal Perturbation Sources KW stratified medium KW internal gravitational waves KW far fields KW surface waves KW uniform asymptotics KW wave front KW Airy function. JO Russian Journal of Earth Sciences AU Vladimirov, I.Y. PY 2023 IS 23 PB Geophysical Center of the Russian Academy of Sciences