@other{https://resolver.caltech.edu/CaltechAUTHORS:20101130-150707270,
    title = "Geometry of Nonlinear Systems : CDS 202 lecture notes",
    year = "2011",
    url = "https://resolver.caltech.edu/CaltechAUTHORS:20101130-150707270",
    id = "record"
}