  The jeep problem was first solved by O. Helmer and N.J. Fine. But not much
later, C.G. Phipps formulated a more general solution. He formulated a
so-called convoy or caravan variant of the jeep problem and reduced the
original problem to it. The convoy idea of Phipps was refined in [3]. Here we
will apply this refined idea to several variants of the jeep problem.
