Jd. Farmer, EXTREME-POINTS OF THE UNIT BALL OF THE SPACE OF LIPSHITZ FUNCTIONS, Proceedings of the American Mathematical Society, 121(3), 1994, pp. 807-813
We consider the space of all Lipschitz functions on a metric space wit
h bounded Lipschitz norm, and give an intrinsic characterization of th
e extreme points of the unit ball. We briefly discuss some examples of
extreme Lipschitz functions, and apply the result to show that if the
norm of a Banach space is Gateaux differentiable then extreme functio
ns on any one-dimensional subspace may be canonically extended to extr
eme functions on the whole space.