@other{https://resolver.caltech.edu/CaltechAUTHORS:20140805-133252590,
    title = "Two-dimensional irrotational mixed subsonic and supersonic flow of a compressible fluid and the upper critical Mach number",
    year = "1945",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:20140805-133252590",
    id = "record"
}


@other{https://resolver.caltech.edu/CaltechAUTHORS:20140805-134608325,
    title = {The "limiting line" in mixed subsonic and supersonic flow of compressible fluids},
    year = "1944",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:20140805-134608325",
    id = "record"
}