@inbook{https://resolver.caltech.edu/CaltechAUTHORS:AHNmgm87,
    title = "Micromechanics of granular materials : proceedings of the U.S./Japan Seminar on the Micromechanics of Granular Materials, Sendai-Zao, Japan, October 26-30, 1987",
    chapter = "Experiments on Chute Flows of Granular Materials",
    year = "1987",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:AHNmgm87",
    id = "record",
    isbn = "0444705236"
}


@inbook{https://resolver.caltech.edu/CaltechAUTHORS:NGUmatbm79,
    chapter = "Funnel Flow in Hoppers",
    year = "1979",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:NGUmatbm79",
    id = "record"
}