Paul Yiu, On the Fermat lines,
Forum Geometricorum 3 (2003) 73--81.
Abstract: We study the triangle formed by three
points each on a Fermat line of a given triangle, and at equal distances
from the vertices. For two specific values of the common distance, the
triangle degenerates into a line. The two resulting lines are the axes
of the Steiner ellipse of the triangle.
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