@other{https://resolver.caltech.edu/CaltechETD:etd-06302006-083245,
    title = "Studies of Amphibolites and Constituent Hornblendes From an Area of Progressive Metamorphism Near Lead, South Dakota",
    year = "1960",
    url = "https://resolver.caltech.edu/CaltechETD:etd-06302006-083245",
    id = "record",
    doi = "10.7907/V56J-JE76"
}