Since at least 1994, he has maintained a list of triangle centers and their properties.

Peter Yff initiated the study of this triangle center in 1987.

The center of the Parry circle is also a triangle center.

Consequently, this invariance is a necessary property for any point being considered as a triangle center.

Hence the 1st isogonic center is also a triangle center.

Therefore this triangle center is none other than the Fermat point.

In the following table of recent triangle centers, no specific notations are mentioned for the various points.

This gives an easy way to create new triangle centers.

For the corresponding triangle center there are four distinct possibilities:

This special property is related to the concept of triangle center also.