@other{https://resolver.caltech.edu/CaltechETD:etd-08292008-105155,
    title = "The magnetic history of solar active regions",
    year = "1977",
    url = "https://resolver.caltech.edu/CaltechETD:etd-08292008-105155",
    id = "record",
    doi = "10.7907/ZPPR-4490"
}