Given a triangle 
, construct the contact
triangle 
.
Then the Nobbs points are the intersections of the corresponding sides of triangles
and 
, i.e., the first Nobbs point 
is the intersection of 
and 
, and similarly for 
and 
. The Nobbs points are collinear
and fall along the Gergonne line. They have trilinear
coordinates 
,
, and 
.
Given the tangent circles of a reference triangle, the pairwise external centers of similitude are the Nobbs points.
