@other{https://resolver.caltech.edu/CaltechTHESIS:04112011-093820974,
    title = "Modeling seismic wave propagation using paraxial extrapolators",
    year = "1991",
    url = "https://resolver.caltech.edu/CaltechTHESIS:04112011-093820974",
    id = "record",
    doi = "10.7907/10tz-eh38"
}