We prove, following [5, p. 92], that any family of subtrees of a finite tree satisfies the Helly property.MML identifier: HELLY, version: 7.8.09 4.97.1001
@article{bwmeta1.element.doi-10_2478_v10037-008-0013-3, author = {Jessica Enright and Piotr Rudnicki}, title = {Helly Property for Subtrees}, journal = {Formalized Mathematics}, volume = {16}, year = {2008}, pages = {91-96}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_v10037-008-0013-3} }
Jessica Enright; Piotr Rudnicki. Helly Property for Subtrees. Formalized Mathematics, Tome 16 (2008) pp. 91-96. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_v10037-008-0013-3/
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