Diener, Francine; Diener, Marc [Chasse au canard. I. Les canards.][1] (French) [Duck hunt. I. The ducks] Collect. Math. 32 (1981), no. 1, 37–74. Benoît, Éric [Chasse au canard. II. Tunnels—entonnoirs—peignes.][2] (French) [Duck hunt. II. Tunnels—funnels—combs] Collect. Math. 32 (1981), no. 2, 77–97. Callot, Jean-Louis [Chasse au canard. III. Les canards ont la vie brève.][3] (French) [Duck hunt. III. Ducks have a short life] Collect. Math. 32 (1981), no. 2, 99–114. Benoît, Éric; Callot, Jean-Louis [Chasse au canard. IV. Annexe numérique.][4] (French) [Duck hunt. IV. Numerical appendix] Collect. Math. 32 (1981), no. 2, 115–119. [1]: http://ams.org/mathscinet-getitem?mr=0643399 [2]: http://ams.org/mathscinet-getitem?mr=0653888 [3]: http://ams.org/mathscinet-getitem?mr=0653889 [4]: http://ams.org/mathscinet-getitem?mr=0653890