Bijective Proofs for "Enumerative Properties of Ferrers Graphs"

Recently, Ehrenborg and Van Willenburg defined a class of bipartite graphs that correspond naturally to Ferrers diagrams, and proved several results about them. We give bijective proofs for the (already known) expressions for the number of spanning trees and (where applicable) Hamiltonian paths of these graphs. Their paper can be found at http://www.ms.uky.edu/~jrge/Papers/Ferrers_graphs.pdf .