Rational approximations to linear forms in values of G-functions Makoto Nagata — 1995 Acta Arithmetica
Diophantine approximations related to rational values of G-functions Makoto Nagata — 2003 Acta Arithmetica
A generalization of the sizes of differential equations and its applications to G -function theory Makoto Nagata — 2001 Annali della Scuola Normale Superiore di Pisa - Classe di Scienze