@article{DCG_1989__4_6_131081,
     author = {Micha Sharir and Janos Pach},
     title = {The {Upper} {Envelope} of {Piecewise} {Linear} {Functions} and the {Boundary} of a {Region} {Enclosed} by {Convex} {Plates:} {Combinatorial} {Analysis.}},
     journal = {Discrete & computational geometry},
     pages = {291--310},
     publisher = {mathdoc},
     volume = {4},
     number = {6},
     year = {1989},
     zbl = {0734.05054},
     url = {http://geodesic.mathdoc.fr/item/DCG_1989__4_6_131081/}
}