@article{https://resolver.caltech.edu/CaltechAUTHORS:20150811-112829955,
    title = "Differentials of Functions with Arguments and Values in Topological Abelian Groups",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1940",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:20150811-112829955",
    id = "record",
    issn = "0027-8424",
    volume = "26",
    pmcid = "PMC1078188"
}


@article{https://resolver.caltech.edu/CaltechAUTHORS:MICpnas35,
    title = {"Riemannian" differential geometry in abstract spaces},
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1935",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:MICpnas35",
    id = "record",
    issn = "0027-8424",
    volume = "21"
}


@article{https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30c,
    title = "Quadratic functional forms in a composite range",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1930",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30c",
    id = "record",
    issn = "0027-8424",
    volume = "16"
}


@article{https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30b,
    title = "The differential geometry of a continuous infinitude of contravariant functional vectors",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1930",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30b",
    id = "record",
    issn = "0027-8424",
    volume = "16"
}


@article{https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30d,
    title = "Projective functional tensors and other allied functionals",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1930",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30d",
    id = "record",
    issn = "0027-8424",
    volume = "16"
}


@article{https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30a,
    title = "Differential geometries of function space",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    year = "1930",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:MICpnas30a",
    id = "record",
    issn = "0027-8424",
    volume = "16"
}