PageHeader : Funkcialaj Ekvacioj, 41 (1998) 133-166 Title : Formal Power Series Solutions of Nonlinear First Order Partial Title : Differential Equations AuthorInfo : By AuthorInfo : Raymond GERARD and Hidetoshi TAHARA AuthorInfo : (Universite Louis Pasteur, France and Sophia University, Japan) section : 1. Preliminaries section : 2. Formulation in partial df.fi erential equations section : 3. Some deffiitions section : 4. Main Theorems section : 5. Some preparatory results section : 6. Proof of theorem 4.3 in case $q(u)=0$ or 1 section : 7. Interpretation of the condition (4.2) section : 8. Proof of theorem 4.3 in case $q(u)\geq 2$ section : 9. Proof of lemma 8.2 section : 10. Proof of lemma 8.3 section : References