# These and adjacent issues are explained in details in several lecture notes and survey papers that I wrote on this subject. For more information you are invited to browse the complete list of (online) papers available on this site.

Yakovenko, S. Quantitative theory of ordinary differential equations and tangential Hilbert 16th problem, Preprint math.DS/0104140 (2001), 1--69, Lecture notes of the course delivered on the Workshop "Asymptotic series, differential algebra and finiteness theorems" (Montreal, 2000), to appear in CRM Proceedings.

Yakovenko, S. On functions and curves defined by ordinary differential equations. The Arnoldfest (Toronto, ON, 1997),  Fields Inst. Communications, 24 (1999), 497--525, Amer. Math. Soc., Providence, RI, 1999

Research report (1996) mentions and briefly surveys some of the previous work

Ilyashenko, Yu., Yakovenko, S. Concerning the Hilbert sixteenth problem. Concerning the Hilbert 16th problem, 1--19, Amer. Math. Soc. Transl. Ser. 2, 165, Amer. Math. Soc., Providence, RI, 1995