@other{https://resolver.caltech.edu/CaltechTHESIS:08292011-141658832,
    title = "Estimation of the radial variation of seismic velocities and density in the earth",
    url = "https://resolver.caltech.edu/CaltechTHESIS:08292011-141658832",
    id = "record",
    doi = "10.7907/K0B1-PW97"
}