  It is known that there exists an order isomorphism between the Weyl group
orbit through a minuscule weight of a simply-laced finite-dimensional simple
Lie algebra and the set of all order filters in a self-dual connected
d-complete poset. In this paper, we try to extend this fact to the case of
multiply-laced finite-dimensional simple Lie algebras by using the "folding"
technique with respect to a Dynkin diagram automorphism.
