Non-existence of distinct codirected locally minimal trees on a plane / K. I. Oblakov. // Vestnik Moskovskogo Universiteta. Seriya 1. Matematika. Mekhanika. 2009. № 2. P. [Moscow Univ. Math. Bulletin. Vol. 72, N 2, 2017. P. 62-66].
Locally minimal graphs on a plane are considered. A simpler proof is given for the uniqueness of a globally minimal spanning tree on a plane in the general case. The proof presented here uses only local minimality of trees and is of independent interest.
Key words: locally minimal tree.