1. Hajja M.: On nested sequences of triangles. Results Math. 54, 289–299 (2009)
2. Hajja M.: Generalized Napoleon and Torricelli transformations and their iterations. Beiträge Algebra Geom. 51, 171–190 (2010)
3. Hajja M., Martini H., Spirova M.: On converses of Napoleon’s theorem and a modified shape function. Beiträge Algebra Geom. 47, 363–383 (2006)
4. Ismailescu D., Jacobs J.: On sequences of nested triangles. Period. Math. Hungar. 53, 169–184 (2006)
5. Johnson, R.A.: Advanced Euclidean Geometry. Houghton Mifflin, New York (1929); reprinted by Dover Publications, New York (1960)