Convex hull and polygon intersection in Prolog

@unpublished{fw-siam85,
    author = "Franklin, Wm. Randolph and Wu, Peter Y. F.",
    title = "Convex hull and polygon intersection in {Prolog}",
    month = "18 Jul",
    year = "1985",
    note = "(presented at SIAM GM\\&R)",
    href = "\bibhref{37-siam85-prolog-hull}"
}