%0 Journal Article %A Sergey Vakulenko %A Dmitry Grigoriev %T Complexity of gene circuits, Pfaffian functions and the morphogenesis problem %J Comptes Rendus. Mathématique %D 2003 %P 721-724 %V 337 %N 11 %I Elsevier %R 10.1016/j.crma.2003.10.021 %G en %F CRMATH_2003__337_11_721_0