1. Ebene Algebraische Kurven;Brieskorn,1981
2. Characteristic roots of stochastic matrices;Dmitriev;Izv. Akad. Nauk SSSR Ser. Mat.,1946
3. On the characteristic roots of matrices with nonnegative elements;Karpelevich;Izv. Akad. Nauk SSSR Ser. Mat.,1951
4. Nonnegative Matrices;Minc,1988