@other{https://resolver.caltech.edu/CaltechTHESIS:07192011-111928416,
    title = "Carleman inequalities and unique continuation for higher order elliptic differential operators",
    year = "1993",
    url = "https://resolver.caltech.edu/CaltechTHESIS:07192011-111928416",
    id = "record",
    doi = "10.7907/ws5h-je24"
}