Dumortier, F. (1978). Singularities of vector fields. IMPA.
Cita Chicago (17th ed.)Dumortier, Freddy. Singularities of Vector Fields. Rio de Janeiro, Brazil: IMPA, 1978.
Cita MLA (9th ed.)Dumortier, Freddy. Singularities of Vector Fields. IMPA, 1978.
Atenció: Aquestes cites poden no estar 100% correctes.