@other{https://resolver.caltech.edu/CaltechETD:etd-01232009-095750,
    title = "A Study of Pressure Drop in Helical Coils",
    url = "https://resolver.caltech.edu/CaltechETD:etd-01232009-095750",
    id = "record",
    doi = "10.7907/GV93-7D64"
}


@other{https://resolver.caltech.edu/CaltechETD:etd-02052009-133758,
    title = "An Experimental Investigation of the Pressure Loss in Flow Through Helical Coils",
    url = "https://resolver.caltech.edu/CaltechETD:etd-02052009-133758",
    id = "record",
    doi = "10.7907/KZ8G-V819"
}