Degree-Preserving Forests. - Hajo Broersma; Andreas Huck; Ton Kloks; Otto R. Koppius; Dieter Kratsch; Haiko Müller; Hilde Tuinstra (MFCS, 1998)

Independence trees and Hamilton cycles. - Hajo Broersma; Hilde Tuinstra (J. Graph Theory, 1998)

Degree-preserving trees. - Hajo Broersma; Otto R. Koppius; Hilde Tuinstra; Andreas Huck; Ton Kloks; Dieter Kratsch; Haiko Müller (Networks, 2000)