Tohutoro APA (7th ed.)

Dumortier, F. (1978). Singularities of vector fields. IMPA.

Tohutoru Kātū Chicago (17th ed.)

Dumortier, Freddy. Singularities of Vector Fields. Rio de Janeiro, Brazil: IMPA, 1978.

Tohutoro MLA (9th ed.)

Dumortier, Freddy. Singularities of Vector Fields. IMPA, 1978.